Palau’s Forest Resources,
2003
Joseph A. Donnegan, Sarah L. Butler,
Olaf Kuegler, Brent J. Stroud,
Bruce A. Hiserote, and Kashgar Rengulbai
Resource Bulletin
PNW-RB-252
January 2007
United States
Department of
Agriculture
Forest
Service
Pacific Northwest
Research Station
The Forest Service of the U.S. Department of Agriculture is dedicated to the principle of
multiple use management of the Nation’s forest resources for sustained yields of wood,
water, forage, wildlife, and recreation. Through forestry research, cooperation with the
States and private forest owners, and management of the National Forests and National
Grasslands, it strives—as directed by Congress—to provide increasingly greater service
to a growing Nation.
The U.S. Department of Agriculture (USDA) prohibits discrimination in all its programs and
activities on the basis of race, color, national origin, age, disability, and where applicable,
sex, marital status, familial status, parental status, religion, sexual orientation, genetic
information, political beliefs, reprisal, or because all or part of an individual’s income
is derived from any public assistance program. (Not all prohibited bases apply to all
programs.) Persons with disabilities who require alternative means for communication of
program information (Braille, large print, audiotape, etc.) should contact USDA’s TARGET
Center at (202) 720-2600 (voice and TDD). To file a complaint of discrimination, write
USDA, Director, Office of Civil Rights, 1400 Independence Avenue, SW, Washington, DC
20250-9410 or call (800) 795-3272 (voice) or (202) 720-6382 (TDD). USDA is an equal
opportunity provider and employer.
Authors
Joseph A. Donnegan is an ecologist, Sarah L. Butler is an ecologist, Olaf
Kuegler is a statistician, and Bruce A. Hiserote is an information management
specialist, Forestry Sciences Laboratory, 620 SW Main Street, Suite 400, Portland,
OR 97205-3028. Brent J. Stroud was the quality assurance technician for the
Portland Forestry Sciences Laboratory, but now works for Interior West Forest
Inventory and Analysis. Kashgar Rengulbai was a forester on Palau.
Abstract
Donnegan, Joseph A.; Butler, Sarah L.; Kuegler, Olaf; Stroud, Brent J.;
Hiserote, Bruce A.; Rengulbai, Kashgar. 2007. Palau’s forest resources, 2003.
Resour. Bull. PNW-RB-252. Portland, OR: U.S. Department of Agriculture,
Forest Service, Pacific Northwest Research Station. 52 p.
The Forest Inventory and Analysis Program collected, analyzed, and summarized
field data on 54 forested plots on the islands in the Republic of Palau. Estimates
of forest area, tree stem volume and biomass, the numbers of trees, tree damages,
and the distribution of tree sizes were summarized for this statistical sample.
Detailed tables and graphical highlights provide a summary of Palau’s forest
resources and a comparison to 1987 data.
Keywords: Palau, biomass, damage, FIA, forest inventory, volume, land cover.
Summary
The Forest Inventory and Analysis (FIA) Program conducted a systematic inventory of the forests of Palau in 2003 to estimate forest area, tree stem volume,
biomass, carbon storage, tree damages, and the percentage cover of understory
vegetation species. Fifty-four permanent field plots were installed, 11 in limestone
forest and 43 in volcanic forest. Land cover was mapped into five broad classes,
forest, nonforest vegetation, urban, barren, and inland water, by using recently
acquired high-resolution satellite imagery. Soil survey information was used to
classify forest into limestone and volcanic types. Our estimates for this inventory
are derived from a sample based on 110,028 acres in Palau, with about 16 percent
of the land classified as limestone forest and 67 percent classified as volcanic forest.
About 2 percent of the landscape was classified as urban land, the majority on
Koror and Babeldaob. We estimated gross tree stem volume to be about 302 million
cubic feet for all size classes including seedlings and saplings. Aboveground dry
biomass for tree stems 5 inches and greater was estimated to be 4.7 million tons.
Approximately 13 percent of the trees sampled in the inventory had some form of
damage. The growth of damaging vines in the crowns of trees was the most prevalent damage type, with conks and lost apical dominance following in prevalence.
The most frequently identified damaging agents were other vegetation, disease, and
weather. Palau’s forests are relatively dense and have high species diversity. A total
of 128 tree species and 132 understory species were measured on FIA plots. The
average number of tree species per sixth-acre plot was 12 in volcanic forest and 10
in limestone forest. Palauan foresters and ecologists were especially helpful with
species identification in the field.
Palau’s Forest Resources, 2003
Introduction
This summary of forest resources on the islands of Palau (fig. 1) was based on a
forest inventory conducted in 2003 by the USDA Forest Service, Pacific Northwest
Forest Inventory and Analysis (FIA) Program in cooperation with Pacific Island
foresters. The inventory is a subset of the national FIA effort and was designed
to help answer local and national questions about the status and trends in tropical forested ecosystems and to share forestry skills among cultures and agencies.
The fieldwork for this inventory was conducted by a multinational crew including
foresters from Palau, American Samoa, and mainland U.S. foresters and ecologists.
This systematic, sample-based field inventory on Palau is an update to prior
inventory work (Cole et al. 1987, MacLean et al. 1988) estimating forest type area,
tree size distribution, and stem volume. New information is included for all forests
on biomass, and damages for living and dead trees. The inventory was designed
to provide resource managers with information about the current situation so they
can better manage their forested and nonforested lands, and manage or mitigate
any changes in the resource. Empirically based knowledge of the status and trends
in forest vegetation can help managers plan sustainable land use practices, plan
sustainable supplies of wood, control invasive species, control erosion, and manage
disturbances such as fire and animal damage.
Objectives
•
•
•
•
Estimate the current area of forest land by forest type group and stand size
class.
Estimate the volume, biomass, and carbon storage for tree species by diameter class.
Estimate the numbers of trees affected by damaging agents, such as insects
and diseases, and estimate the numbers of dead trees.
Share measurement and analysis techniques among groups involved in the
inventory.
Methods
Site Description
Palau is well known for its tremendous diversity and concentration of both terrestrial and marine life along the network of coral reefs and the chain of more than 300
raised limestone and volcanic islands. The chain of islands runs from the northeast
to southwest for a distance of about 125 miles, approximately 470 miles east of
the Philippines. The islands range in size from the relatively large, volcanic island
RESOURCE BULLETIN PNW-RB-252
Figure 1—The Republic of Palau is in the North Pacific Ocean approximately 470 miles east of the Phillipines. Land cover was
mapped from 2005 QuickBird satellite data.
Palau’s Forest Resources, 2003
of Babeldaob, at about 92,000 acres, to coral rocks topped with trees, only a few
yards across. The tremendous marine diversity is supported by the convergence of
oceanic currents and the filtering and nutrient effects of the dense terrestrial forests.
The topography of the four volcanic islands is marked by steep slopes and rolling
hills, with mangroves often found on coastal flats. The limestone coral islands or
“Rock Islands” support a diversity of tree species on often surprisingly shallow
soils deposited in the recesses of the rugged karstic topography. The highest point
in Palau is the approximately 700-foot-tall Mount Ngerchelchuus on Babeldaob
(Palau Conservation Society).
The climate of Palau is hot and humid with little annual variation in the mean
maximum temperature of 87.9 °F and the mean minimum of 75.6 °F (fig. 2). Total
annual precipitation averages 147.3 inches. In the wettest months, June and July,
monthly precipitation averages 17.04 inches, whereas during the driest months,
February, March, and April, monthly precipitation averages 8.84 inches (data from
Western Regional Climate Center 2004). During an El Niño year (warm phase of
the Southern Oscillation), rainfall tends to be above average for that summer and
below average in the following autumn and winter months (Climate Prediction
Center 2005).
Palau borders the typhoon belt in the western tropical Pacific and is subject to
occasional typhoon damage. Prior to European contact, extensive terracing was
practiced on Babeldaob in upland areas. Paleoenvironmental evidence suggests
terracing may have contributed to landcover change from forest to savanna and
fernland, and accelerated erosion as much as 2,500 years before present (Athens
and Ward 2002). Additional recent disturbances have included mining of bauxite,
military action during World War II (which denuded much of Peleliu and Angaur),
and conversion of forest for agriculture. Forest was cleared during the recent
construction of a new capitol on Babeldaob and a road to encircle the island. Barren
volcanic soils pose high risk of erosion with frequent, intense rainfall and are often
a corridor for colonization by invasive species.
Vegetation Types
The flora of Palau shares many common elements with that of east-Asian and
Indo-Malesian floras (Mueller-Dombois and Fosberg 1998). Species composition in
Palau is distinctive depending on the parent material the soil is derived from, with
volcanic soils found in the north (Babeldaob, Arakabesang, Malakal, and Oreor),
and limestone soils on Peleliu, Angaur, and the Rock Islands to the south. Where
volcanic soils are deposited along coastal flats, mangrove and freshwater swamps
are common. The volcanic islands also support a shrubby, strand vegetation, a
RESOURCE BULLETIN PNW-RB-252
Figure 2—(A) The annual maximum and minimum temperatures in Palau do not fluctuate markedly. However, (B) precipitation is
highly variable throughout the year with a distinct summer wet season and a dry early spring (Western Regional Climate Center 2004).
Palau’s Forest Resources, 2003
closed-canopy interior volcanic forest, ravine and riparian forest, and savanna and
fernland on degraded soils (Mueller-Dombois and Fosberg 1998). The southern,
raised limestone islands support evergreen, closed-canopy forest that is generally
quite species rich and variable from island to island (Cole et al. 1987). Note that the
current report does not describe the vegetation of the Southwest Islands of Palau,
approximately 400 miles southwest of Babeldaob. Additionally, the FIA inventory
does not provide sufficient plot density to reliably classify vegetation types in these
highly diverse tropical forests, but provides plot-level data to help refine remotely
sensed estimates of forest type acreage and developmental stage. Some of the
species named in the following vegetation descriptions (from Cole et al. 1987, and
Mueller-Dombois and Fosberg 1998) were not identified on the 2003 sample of FIA
field plots, either owing to their absence, their understory cover not meeting the 3
percent threshold, or possible misidentification. The FIA and local island staff were
trained by regional botanical experts, and when species could not be identified in
the field, they were sent for expert identification. However, misidentification in the
field remains a possibility.
Volcanic Forest Types
Mangrove—
Mangroves play a vital role in buffering the effects of storms and waves along
coastal areas. They also provide habitat for marine life and filter runoff exiting
terrestrial ecosystems. The filtration that mangroves provide helps to sustain
coral reef and fish habitat by trapping sediment. The mangroves of Palau are a
particularly species-rich mangrove type that extends along a narrow strip of the
tidal zone. The species found here include Rhizophora mucronata, Rhizophora
apiculata, Bruguiera gymnorrhiza, Ceriops tagal, Sonneratia alba, Avicennia
marina, Lumnitzera littorea, Xylocarpus granatum, Scyphiphora hydrophyllacea,
Dalbergia candenatensis, Derris trifoliata, Nypa fruticans, Acrostichum aureum,
and Nephrolepis acutifolia (see table 1 for common and scientific names with
authorities). Mangroves are very dense forest types where left undisturbed.
Swamp forest—
This forest type tends to occur slightly inland of mangrove in areas of fresh or
slightly brackish water. Horsfieldia amklaal, Cynometra ramiflora, Barringtonia
racemosa, Campnosperma brevipetiolata, and Heritiera littoralis are often found
in the intact freshwater swamps, whereas Hibiscus tiliaceus is found in disturbed
areas.
Scientific name
Common name
Aglaia palauensis Kaneh.
Allophylus ternatus (Forst.) Radlk.
Allophylus timorensis (DC.) Bl.
Alphitonia carolinensis Hosok.
Annona reticulata L.
Areca catechu L.
Artocarpus mariannensis Trec.
Astronidium palauense (Kaneh.) Mgf.
Avicennia marina (Bl.) Bakh.
Badusa palauensis Valeton
Barringtonia racemosa (L.) Spreng.
Bruguiera gymnorrhiza (L.) Lam.
Buchanania palawensis Lauterb.
Calophyllum inophyllum L.
Calophyllum pelewense P. F. Stevens
Calophyllum soulattri Burm. f.
Calophyllum sp. L.
Campnosperma brevipetiolata Volk.
Canarium hirsutum Willd.
Casearia cauliflora Volk.
Casearia sp. Jacq.
Casuarina equisetifolia L.
Cerbera floribunda K. Schum.
Cerbera manghas L.
Cocos nucifera L.
Commersonia bartramia (L.) Merr.
Cordia micronesica Kaneh. & Hatus.
Cyathea lunulata (Forst. f.) Copel.
Diospyros ferrea (Willd.) Bakh.
Diospyros sp. L.
Dodonaea viscosa (L.) Jacq.
Dracaena multiflora L.
Drypetes nitida Kaneh.
Dysoxylum sp. Blume
meseoes
chebeludes
ebeludes, chebeludes
elebiob, elebiong
ngel ra ngebard
buuch, betel nut
ebiei, wild breadfuit
meskui
dadaiit
ralm
koranges
kadeges, denges, adeges
geloagl
laurel
chesemoroch
olebtaches, chesemoroch
kelela charm, kiu
mesechaues
kevert
ngas, ironwood
emeridech
emeridech
lius, coconut
aspitan, eremallueang
eluu, tree fern
keuelt
Number
measured
23
3
1
50
1
6
4
32
2
29
51
43
10
34
20
6
6
72
11
1
7
6
2
19
26
7
1
46
10
10
6
14
4
13
Estimated
number
(≥1 inch
diameter)
847,803
36,989
12,330
1,531,290
12,330
73,977
48,518
1,641,189
24,659
897,973
3,407,461
1,095,193
405,607
1,184,578
608,511
356,489
61,247
1,133,048
553,209
12,330
84,906
24,259
24,659
362,987
318,967
165,915
12,330
634,436
393,478
544,171
73,177
878,093
187,882
1,572,844
Standard
error for
estimated
number (±)
431,384
37,027
12,342
803,629
12,342
74,055
35,710
590,773
24,685
582,173
2,020,608
671,454
253,723
579,030
363,048
332,521
45,601
372,006
439,687
12,342
93,158
17,855
17,251
187,580
175,394
153,955
12,342
212,213
357,921
302,309
34,397
397,272
180,779
901,519
Gross
volume
(≥5 inches
diameter)
1,783,505
206,199
29,280
4,434,129
62,771
292,165
5,140,163
1,169,439
1,422,693
3,048,028
2,986,606
5,542,897
1,308,999
5,436,901
1,040,719
480,790
1,910,972
22,836,047
1,072,970
157,802
626,648
1,436,905
281,010
2,378,467
8,416,588
29,882
312,315
1,985,641
384,300
717,026
1,642,371
459,125
373,021
64,752
Standard
error for
estimated
volume (±)
1,359,572
206,415
29,311
1,662,961
62,836
292,472
4,028,666
460,600
1,424,186
2,276,642
1,838,290
2,800,425
1,155,922
3,643,184
654,142
342,400
1,635,495
6,496,431
1,081,278
157,967
687,549
1,536,233
234,815
906,798
4,303,993
29,913
312,643
633,206
270,515
458,131
831,416
279,546
309,627
64,820
RESOURCE BULLETIN PNW-RB-252
Table 1—Scientific names, common names, estimated number and gross volume, and standard errors for estimated totals of species
measured as trees on Palau
Table 1—Scientific names, common names, estimated number and gross volume, and standard errors for estimated totals of species
measured as trees on Palau (continued)
Scientific name
dekemerír
roro
mesekerrak, java plum
rebotel
kesiil
ksid
oseked
tilol
tilol
kalngebard ra belau
blancheos
belau
chebouch, akaboek
dokou
demailei, ebouch
cheramal
emeklachel, eumail
ersachel
ersachel
keam, boui
dort
ngemoel, mekekad
Number
measured
1
49
1
23
20
65
7
1
19
2
9
21
12
40
30
3
26
3
22
49
6
3
9
3
5
11
25
25
24
101
5
1
20
1
12,330
1,419,038
12,129
974,799
381,553
3,017,755
648,639
153,586
172,613
165,915
1,096,866
1,388,568
995,490
2,457,435
650,797
36,989
1,565,282
178,245
825,997
1,027,314
73,977
460,757
97,036
36,388
60,647
700,649
2,709,590
1,003,150
1,002,188
3,852,198
626,672
12,330
381,553
12,330
Standard
error for
estimated
number (±)
12,342
530,051
13,308
753,514
251,122
1,068,888
313,824
153,747
76,502
153,955
936,957
780,722
741,721
969,319
298,347
37,027
776,102
166,261
495,311
537,789
51,752
461,240
106,466
39,925
66,541
641,212
2,248,657
563,395
567,747
1,132,578
614,824
12,342
267,583
12,342
Gross
volume
(≥5 inches
diameter)
64,508
6,648,512
600,183
1,960,664
4,324,582
6,011,868
130,011
—
2,248,390
409,933
3,187,214
751,255
725,013
2,520,347
2,603,796
261,379
1,201,069
93,117
4,368,123
4,916,499
1,315,262
—
518,759
360,357
1,714,517
404,770
375,843
5,112,032
10,735,352
13,722,763
42,993
29,390
8,903,896
127,232
Standard
error for
estimated
volume (±)
64,575
2,094,414
658,512
1,472,100
2,660,022
3,482,031
76,791
—
1,098,577
410,364
3,429,467
355,672
655,318
1,145,401
1,020,943
261,653
508,131
65,804
2,646,783
1,349,345
959,938
—
569,175
395,379
1,881,143
332,830
273,510
4,154,971
9,640,055
5,211,646
43,038
29,421
6,152,703
127,365
Palau’s Forest Resources, 2003
Elaeocarpus graeffei Seem.
Elaeocarpus joga Merr.
Erythrina fusca Lour.
Eugenia cumini (L.) Druce
Eugenia javanica Lam.
Eugenia reinwardtiana (Bl.) DC.
Eugenia sp. L.
Evodia sp.
Fagraea ksid Gilg and Bened.
Ficus sp. L.
Ficus tinctoria Forst. f.
Flacourtia rukam Zoll. & Moritzi
Garcinia matudai Kaneh.
Garcinia rumiyo Fosb.
Garcinia sp. L.
Gironniera celtidifolia Gaudich.
Glochidion ramiflorum Forst.
Glochidion sp. J.R. & G. Forst.
Gmelina elliptica Sm.
Gmelina palawensis H. J. Lam.
Gmelina sp. L.
Guettarda speciosa L.
Gulubia palauensis (Becc.) Moore & Fosb.
Hernandia sonora L.
Hernandia sp. L.
Heterospathe elata (Becc.) Becc.
Hibiscus tiliaceus L.
Horsfieldia amklaal Kaneh.
Horsfieldia novo-guineensis Warb.
Horsfieldia palauensis Kaneh.
Horsfieldia sp. Wild.
Inocarpus fagifer (Park.) Fosb.
Intsia bijuga (Colebr.) O. Ktze.
Lumnitzera littorea (Jack) Voigt
Common name
Estimated
number
(≥1 inch
diameter)
Scientific name
Common name
Macaranga carolinensis Volk.
Manilkara udoido Kaneh.
Manilkara zapota (L.) P. v. Roy.
Morinda citrifolia L.
Morinda latibracteata Val.
Morinda pedunculata Val.
Morinda sp. L.
Mussaenda frondosa L.
Neonauclea forsteri Merrill
Nephelium lappaceum L.
Osmoxylon oliveri Fosberg & Sachet
Osmoxylon sp.
Pandanus aimiriikensis Mart.
Pandanus dubius Spr.
Pandanus kanehirae Mart.
Pandanus palawensis Mart.
Pandanus tectorius Park.
Pandanus utiyamai Kaneh.
Pangium edule Reinw. ex Bl.
Parinari corymbosum (Bl.) Miq.
Parinari laurina Gray
Parinari sp.
Pinanga insignis Becc.
Pithecellobium dulce (Roxb.) Benth.
Pongamia pinnata (L.) Merr.
Pouteria calcarea (Hosok.) Fosb.
Pouteria obovata (R. Br.) Baehni
Pouteria sp. Aubl.
Premna obtusifolia R. Br.
Pterocarpus indicus Willd.
Ptychosperma palauensis (Kaneh.) Moore & Fosb.
Rhizophora apiculata Bl.
Rhizophora mucronata Lam.
Rhus taitensis Guill.
bedel
udeuid
sapodilla
ngel
kesengelengel, ngel
kesengelengel
rambutan, rambotang
ertochet
beku, ongor
buuk
ongor
ongor
riamel
bkau, apgau
eritem, gritin
ebouch, demailei
kamatsiri, opiuma
kisaks
elangel
elangel
osem
las
esbuuch
bngaol
tebechel
eues
Number
measured
49
29
6
8
5
1
3
1
3
1
3
9
25
21
6
1
13
1
2
63
56
4
240
4
1
3
37
1
9
2
8
129
31
40
Estimated
number
(≥1 inch
diameter)
5,074,421
283,579
73,977
946,172
61,648
12,330
36,989
153,586
460,757
12,330
178,245
675,990
3,130,866
810,575
202,904
153,586
559,393
12,330
24,659
2,008,183
2,086,261
331,830
11,655,307
465,410
151,094
36,989
855,954
12,330
381,148
24,659
239,892
3,657,133
365,084
714,045
Standard
error for
estimated
number (±)
1,760,927
173,439
62,652
352,952
50,610
12,342
37,027
153,747
461,240
12,342
155,148
639,395
1,232,969
608,016
190,886
153,747
274,312
12,342
24,685
672,025
1,251,377
223,617
2,337,956
510,641
165,778
37,027
637,145
12,342
309,108
24,685
240,144
2,280,225
327,871
251,240
Gross
volume
(≥5 inches
diameter)
671,260
2,085,556
1,296,562
132,139
211,608
81,626
127,267
—
—
100,828
65,896
145,875
272,360
897,251
332,031
—
463,602
1,050,209
237,335
21,934,439
5,980,513
66,714
8,329,960
80,161
—
160,981
4,146,921
59,315
246,764
917,560
329,740
8,538,981
2,265,232
5,850,777
Standard
error for
estimated
volume (±)
357,840
1,209,721
1,181,412
99,769
165,154
81,712
127,400
—
—
100,934
65,965
86,232
167,696
621,269
262,594
—
464,088
1,051,312
237,584
7,016,031
3,010,760
48,675
1,802,335
87,951
—
161,150
1,701,642
59,377
165,406
918,523
330,086
5,332,588
1,681,146
2,434,616
RESOURCE BULLETIN PNW-RB-252
Table 1—Scientific names, common names, estimated number and gross volume, and standard errors for estimated totals of species
measured as trees on Palau (continued)
Table 1—Scientific names, common names, estimated number and gross volume, and standard errors for estimated totals of species
measured as trees on Palau (continued)
Scientific name
Rinorea carolinensis Kaneh.
Semecarpus venenosus Volk.
Sonneratia alba J. E. Sm.
Stemonurus ammui (Kaneh.) Sleumer
Swietenia macrophylla King
Swietenia mahagoni (L.) Jacq.
Symplocos racemosa Roxb.
Tecoma stans (L.) Juss. ex HBK.
Terminalia catappa L.
Theobroma cacao L.
Timonius subauritus Fosberg & Sachet
Tournefortia argentea L. f.
Trichospermum ledermannii Burret
Vitex cofassus Reinw. ex Bl.
Xylocarpus granatum Koen.
Unknown 0
Unknown 1
Unknown 2
Unknown 3
Unknown 5
Unknown 11
Unknown, other
Total
Common name
tonget
urur
ngmui
honduras mahogany
mahogany
beach almond, miich
suklatei, cocoa
rirs, tree heliotrope
elsau
bars, beokel
meduulokebong
Number
measured
Estimated
number
(≥1 inch
diameter)
Standard
error for
estimated
number (±)
Gross
volume
(≥5 inches
diameter)
Standard
error for
estimated
volume (±)
1
58
52
5
5
8
19
1
4
5
19
4
11
9
16
13
6
2
4
7
1
7
12,129
2,266,927
5,959,545
61,648
202,904
381,148
829,575
153,586
49,318
61,648
1,595,842
48,918
252,222
110,966
338,528
188,082
331,630
307,171
24,659
85,906
12,330
36,989
13,308
689,153
3,934,040
61,712
179,561
345,648
509,114
153,747
38,757
61,712
1,090,534
36,301
167,347
111,082
292,559
168,017
215,243
307,493
17,251
67,207
12,342
20,875
44,758
6,877,953
11,503,833
3,215,714
327,606
414,720
224,606
—
805,001
617,845
925,779
327,509
1,067,694
5,134,682
1,399,499
120,479
37,791
—
228,639
513,431
126,165
1,657,879
49,108
2,306,382
11,491,789
3,219,089
235,724
307,348
143,427
—
657,530
618,494
614,886
270,923
945,028
5,140,070
1,140,977
85,328
32,354
—
188,570
452,329
126,298
1,471,197
2,248
96,594,950
6,639,026
268,511,801
26,355,589
Palau’s Forest Resources, 2003
RESOURCE BULLETIN PNW-RB-252
Interior volcanic forest—
Occurring primarily on volcanic substrates, interior volcanic forest encompasses
distinct subtypes of forest in undisturbed ecosystems. Moving inland from the
mangroves and swamps, the dominant species include Casuarina equisetifolia and
Pandanus tectorius. Farther inland, the forest grades into a mixed-forest canopy
that includes Campnosperma brevipetiolata, Horsfieldia amklaal, H. palauensis,
H. novo-guineensis, Myristica insularis, Parinari laurina, Parinari corymbosum,
Serianthes kanehirae, Glochidion macrosepalum, G. ramiflorum, Alphitonia
carolinensis, Calophyllum inophyllum var. wakamatsui, C. soulattri, C. pelewense,
Symplocos racemosa var. palauensis, Cerbera floribunda, Manilkara udoido, and
Fagraea ksid. The forest is dense, multilayered, and structurally complex here.
Ravine and riparian forest—
In the complex terrain of Palau’s savannas, ravines often break up the open forest
and grassland with narrow strips and sheltered hillsides of more dense and diverse
forest vegetation occurring in relatively moist areas. Barringtonia racemosa and the
poison tree (causes a severe skin rash) Semecarpus venenosus are common components of the ravine and riparian type.
Limestone forest type
On the limestone substrate of Peleliu, Angaur, and the Rock Islands, organic
matter from the vegetation forms a thin layer in places over the coral rock. The
limestone substrate is often steep, porous, and extremely rugged. Rock that borders
the ocean is often undercut by waves and bioerosion, making access difficult. A
species-rich and structurally diverse forest forms here with the dominant species
Intsia bijuga, Psychotria spp., Clerodendron inerme, Eugenia reinwardtiana,
Morinda latibracteata, Garcinia matudai, G. rumiyo var. clacicola, Rinorea sp.,
Cycas circinalis, Flacourtia rukam var. micronesica, Aidia cochinchinensis,
Meryta senfftiana, Polyscias grandifolia, Geniostoma sessile, Premna serratifolia,
Cyrtandra todaiensis, Guettarda speciosa, Badusa palauensis, Psychotria
hombroniana, Ixora casei, and Tarenna sambucina.
Field Methods
The Palau inventory was based on the FIA inventory design that was implemented
across the mainland United States beginning in 2000. Adaptations were made
to the national design to include additional branching and rooting forms, using
topography to define site productivity or drought resilience (in perhumid climates),
additional tree crown measurements, and including special-interest species ranging
from invasive plants to pathogens to culturally or economically important species
10
Palau’s Forest Resources, 2003
of various life forms. In the mainland FIA Program, plots are spaced within forest
land on a 3.3-mile grid. With the assistance of the Government of Palau, Bureau of
Agriculture, plots were spaced across all vegetation types at approximately 1.9-mile
intervals, yielding a triple intensification of the mainland inventory plot grid.
The FIA plot-cluster is composed of four 24-foot-radius subplots (fig. 3). Three
of those subplots are equally spaced, as if on spokes of a wheel, around the central
subplot. The distance from the middle of the central subplot to the middle of each
subplot on the three spokes was 120 feet.
Forest Inventory and Analysis
Pacific Islands Plot Design
Overall plot footprint: ~1.5 acres
Distance between subplot centers: 120 feet
Distance from subplot center to microplot center: 12 feet
Key
6.8-foot-radius microplot:
seedlings + saplings
24-foot-radius subplot:
all trees (5 inches
diameter at breast height)
Plot
2
Subplot
Microplot
N
1
4
3
Figure 3—Forest Inventory and Analysis Pacific Islands plot design.
11
RESOURCE BULLETIN PNW-RB-252
A variety of information was collected at the plot, subplot, and tree levels
(USDA Forest Service 2003). Differences in forest-type conditions are also mapped.
For example, roads that intersect subplots are mapped, as are clear boundaries in
forest tree size classes. The primary variables collected include plot location, slope,
aspect, elevation, subplot slope position and shape, tree species, diameters, heights,
damages, branching and rooting forms, decay, epiphytic loadings, crown characteristics, tree locations, and regeneration information. The fieldwork for this inventory
was performed February to April 2003.
Analysis Methods
The FIA estimates of forest land are based on a system that uses aerial photography
or satellite imagery to define different types of land (strata) across the landscape.
The simplest stratification is separating land into forest and nonforest strata.
However, stratifications can be assisted or refined by using ancillary data such as
topography, soil information, life zone or climatically based information, and prior
inventories of vegetation groups.
The Palau stratification for estimating numbers of trees, volume, biomass,
and carbon was conducted via a classification of 2003 IKONOS satellite data. The
initial land-cover classification divided the landscape into forest, urban, nonforest
vegetation, barren, and water cover types. At least 10 percent cover of trees was
used as the basis for the forest-land classification, and includes both agroforests and
mangrove forests. Nonforest vegetation includes other vegetation types with less
than 10 percent cover of trees. A geographic information system (GIS) was used to
sum acreage for each type. Forest was further classified into volcanic and limestone
forest types by overlaying a soils layer (USDA Natural Resources Conservation
Service 1983) on the land-cover-classification layer in a GIS. We used the GIS to
individually sum the acreage of limestone and volcanic forest types. From this
limestone/volcanic stratification, field plot condition types were expanded to the
landscape level. The acreage each field plot represents was derived by dividing
the total acreage of forest in each of the limestone and volcanic soil types by the
number of field plots that fell within the geographic bounds of that specific type.
Average stand size was expanded from the plots to the landscape level by using the
same expansion factors.
Land cover was further refined into more detailed classes through an ongoing cooperative project with the USDA Forest Service, Pacific Southwest Region,
Remote Sensing Laboratory. Both the 2003 IKONOS and 2005 QuickBird satellite
imagery were used for the detailed mapping and served as the basis for land cover
estimates.
12
Palau’s Forest Resources, 2003
Wood volume was estimated for individual trees by using tree height and two
stem diameter measurements. These measurements are expanded to tree-level
volume estimates by using equations for sections of a cone. Both gross stem volume
and net stem volume estimates were calculated. Net stem volume subtracts damage
and rotten defects from gross stem volume. Biomass for individual tree stems was
estimated by using the specific gravity for known species (30 out of 129 species
measured on Palau have known specific gravities). For species where specific gravity was not known, an average specific gravity, according to forest type, was used.
These estimates of aboveground tree biomass are derived from bole volume and
include only biomass for the main stem, excluding branches, roots, and foliage.
An additive combination of relative density and relative basal area (importance
value) was used to classify forest types and assess the species dominance in a stand.
Traditional site productivity estimates require forest stand age, derived from the
annual rings of forest trees. Because tropical trees do not produce consistent annual
rings, a modified topographic relative moisture index (TRMI) (Parker 1982) was
examined as a proxy for site productivity. The TRMI used a weighted, additive
combination of slope steepness, slope shape, and slope position to assess the potential moisture retention in a forested stand. Remeasurement data from these plots at
the next inventory cycle will provide a better estimate of productivity than TRMI.
In very wet environments like Palau, TRMI may be best considered a drought
resilience proxy, predicting where soil and water accumulates, owing to topography,
across a landscape. We also recognize moisture is not likely to be the only factor
limiting tree growth and that a prolonged excess of moisture can be detrimental to
the growth of many tree species.
Reliability of FIA Data
The area of forested land cover types classified from the IKONOS satellite imagery
was assumed to be accurate and was used as the basis for the expansion of the
numbers of trees, tree volume, and tree biomass from the plot scale to the foresttype scale. Possible sources of error not accounted for in our estimates include
errors in the land cover map owing to incorrect interpretation of the image, errors
from rounding when working with pixel-based imagery, and measurement errors on
field plots. Standard errors for the expansion of our estimates from field plots to the
forested landscape were calculated according to the proportion of area occupied by
either volcanic or limestone forest types. Volcanic and limestone forest areas were
treated as known rather than estimated, and variance was calculated by using methods in Cochran (1977). Using one standard error as our basis for evaluation gives a
68 percent chance that the true total gross tree stem volume on Palau lies between
13
RESOURCE BULLETIN PNW-RB-252
275,061,708 and 329,711,230 cubic feet. There is a 68-percent chance that the true
number of trees (>1 inch diameter) on Palau lies within the range of 89,955,926 to
103,233,978. Readers are cautioned to examine the standard errors associated with
species-level estimates for the number of individuals and volume by tree species in
table 1.
Resource Highlights
Land Cover
Palau is currently about 82 percent forested, which includes agroforest and secondary forest vegetation (table 2). About 2 percent of the landscape was classified as
urban land and about 14 percent was classified as nonforest vegetation including
savanna and agricultural lands. The area for land cover estimates totaled 110,028
acres.
A prior vegetation survey (Cole et al. 1987) delineated vegetation types by
using 1976 aerial photography, and estimated forest cover to be 80 percent of total
land, including secondary vegetation and agroforest (table 2). Nonforest vegetation
was estimated to be about 20 percent of the total land cover. Total acreage calculated from the Cole et al. (1987) maps that FIA recently scanned and digitized was
101,851 acres.
The methodology and the area sampled for land cover estimates differ from
those used for prior estimates. The Cole et al. (1987) work surveyed and mapped
less limestone forest and defined forested lands on the basis of a canopy cover of
approximately ≥ 30 percent. The recent effort used a forest-land canopy threshold
of ≥ 10 percent to remain consistent with national FIA standards and the recent FIA
work in American Samoa and Guam. In the current survey we mapped roads as
urban land.
To compare similar sample areas on Palau, we summarized land cover area
on an island-by-island basis for Babeldaob, Peleliu, Angaur, and Koror (fig. 4).
Although the difference in canopy cover thresholds between 1987 and 2005 still
exists, trends suggest there may be some areas of Babeldaob where nonforest
vegetation has reverted to forest. On Peleliu and Koror, it appears that forest land
is being converted to urban and nonforest vegetation uses. These observations are
tentative pending a thorough analysis of land cover change for Palau.
14
Palau’s Forest Resources, 2003
Table 2—Estimated area by land cover, 1976 a and 2005
Land cover
1976
Limestone forestb
Volcanic forest
9,626
71,948
Total forest land c
Acres
17,316
73,369
81,574
90,685
1,550
18,250
339
139
2,433
15,329
1,103
64
414
20,277
19,343
101,851
110,028
Nonforest and other areas:
Nonforest urban
Nonforest vegetation
Barren lands
Unclassified
Water
Total nonforest and other land
Total area in survey
2005
a Figures for maps derived from 1976 aerial photography differ slightly from
those published by Cole et al. (1987). Figures here were derived by scanning the
historical maps and aggregating area totals with a geographic information system.
b The sample area for forest cover, especially limestone types, was increased
between the 1976 and 2005 remotely sensed imagery.
c Forest land includes agroforest and secondary forest vegetation.
60,000
40,000
1988
2005
2,000
1,500
500
0
0
F
N ore
o n st
ve fo
ge re
t a st
tio
Ba n
r re
n
U
rb
an
W
at
er
U
nk
no
w
n
To
ta
l
Land cover
2,000
2,500
1988
2005
2,000
Acres
3,000
Land cover
Peleliu
1,500
1,000
500
0
0
Land cover
Angaur
1988
2005
F
N ore
o n st
ve fo
ge re
t a st
tio
Ba n
r re
n
U
rb
an
W
at
er
U
nk
no
w
n
To
ta
l
1,000
F
N ore
o n st
ve fo
ge re
t a st
tio
Ba n
r re
n
U
rb
an
W
at
er
U
nk
no
w
n
To
ta
l
Acres
4,000
1988
2005
1,000
20,000
5,000
Koror
2,500
F
N ore
o n st
ve fo
ge re
t a st
tio
Ba n
r re
n
U
rb
an
W
at
er
U
nk
no
w
n
To
ta
l
Acres
80,000
3,000
Babeldaob
Acres
100,000
Land cover
Figure 4—Forest land on Babeldaob is maturing and may be encroaching slightly on nonforest vegetation. On Peleliu, Koror, and
Angaur, forest land is being lost to urban and nonforest vegetation land uses. Conversion of forest to urban land use is also expected
on Babeldaob upon completion of the circumnavigating “Compact Road” in 2006, that will open areas previously inaccessible.
15
Productivity and Drought Resilience
Site productivity estimates are difficult to obtain in tropical environments owing
to a lack of consistent annual tree rings. The standard premise for site productivity
hinges on determining how height or diameter changes with respect to tree age
under particular site conditions. Remeasurement of individual trees at the next
inventory cycle will provide better estimates of site productivity by using growth
over the specific period. For the present work, we attempted to estimate productivity as an additive index based on a site’s potential moisture accumulation owing
to local topography (TRMI) (Parker 1982). However, in a region of such high
precipitation, as in Palau, the TRMI estimate of productivity may be much less
reliable than productivity estimates based on detailed soil mapping. For example,
differences among forest, savanna, and fernland topsoils are dramatic with respect
to soil organic matter, cation exchange capacity, and potential aluminum toxicity
for plant growth, with a succession of soil degradation occurring from forest soils
to savanna and fernland soils through processes of land clearing, repeated burning,
and subsequent erosion and leaching of topsoil nutrients (Smith and Babik 1988).
The topographic relative moisture index may have utility in very wet environments
as a predictor of resilience to occasional drought, because TRMI predicts moisture
accumulation (and likely sediment/soil accumulation as well) based on topography.
Using TRMI in this context, we classified approximately 58 percent of the forested
lands in Palau as medium high to highest drought resilience (fig. 5). This relatively
high percentage owes to much of the land on Babeldaob being gently sloping
volcanic soils, and thus drought resilience on these lands is expected to be relatively
high. Babeldaob represents approximately 80 percent of our inventory area. On the
limestone and limestone-derived soils of the Rock Islands, resilience to drought
would be expected to be less based on lower moisture retaining capacities of these
well-drained, often shallow soils and the complex karst topography. However,
aluminum toxicity to plants is not expected on limestone-derived soils, whereas
it is likely to limit plant growth in degraded volcanic-derived soils.
Forest Structure
Forest Inventory and Analysis estimates stand size class on forested field plots
to capture the predominant diameter of live trees in forest stands. In Palau the
dominant size class for volcanic forest types tends to be small, in the 5- to 11-inch
diameter category (table 3, fig. 6). Limestone forest types tend to be dominated by
slightly larger trees, in the 11- to 20-inch category (fig. 6). No plots were sampled
on limestone soils that included stands in the smallest diameter category of 1 to 5
inches.
16
Forest land potential drought resilience
(Percentage of total forest area and acreage)
10%
10,055
6%
5,940
13%
12,260
Low
Medium low
Medium
29%
28,546
23%
21,973
Medium high
High
Highest
19%
17,915
Figure 5—A topographic relative moisture index was used to predict drought resilience
in the perhumid climate of Palau. On the gentle slopes and relatively deep volcanic soils
of the largest island, Babeldaob (approximately 80 percent of forested acreage on Palau),
drought resilience is expected to be higher than in the raised limestone Rock Islands.
The diameter distribution for trees on Palau is heavily weighted toward
small-diameter trees (fig. 7). This “reverse-J” distribution of tree diameter is
typical where regeneration is abundant. Through time, many small trees die before
they grow into the larger diameter classes. For trees at least 5 inches in diameter,
tree heights are predominantly in the 30- to 50-foot height classes (fig. 8). The
tallest tree on an FIA plot, a Horsfieldia sp., measured 44 inches in diameter and
approximately 114 feet tall.
Wood volume (fig. 9, tables 4, 5, and 6), biomass (fig. 10, table 7), and carbon storage (table 8) follow a similar distribution as the “reverse-J” seen for the
number of trees according to diameter (fig. 7). Most of the volume, biomass, and
carbon is accounted for in the smaller diameter classes owing to the relatively
high number of trees in those size classes. (Text continues on page 33.)
17
18
Table 3—Estimated number of live trees on forest land by species and diameter class
Diameter class (inches)
Species
Aglaia palauensis
Allophylus ternatus
Allophylus timorensis
Alphitonia carolinensis
Annona reticulata
Areca catechu
Artocarpus mariannensis
Astronidium palauense
Avicennia marina
Badusa palauensis
Barringtonia racemosa
Bruguiera gymnorrhiza
Buchanania palawensis
Calophyllum inophyllum
Calophyllum pelewense
Calophyllum soulattri
Calophyllum sp.
Campnosperma brevipetiolata
Canarium hirsutum
Casearia cauliflora
Casearia sp.
Casuarina equisetifolia
Cerbera floribunda
Cerbera manghas
Cocos nucifera
Commersonia bartramia
Cordia micronesica
Cyathea lunulata
Diospyros ferrea
Diospyros sp.
Dodonaea viscosa
Dracaena multiflora
Drypetes nitida
Dysoxylum sp.
Elaeocarpus graeffei
Elaeocarpus joga
Erythrina fusca
Eugenia cumini
Eugenia javanica
Eugenia reinwardtiana
Eugenia sp.
Evodia sp.
≤5.0
5.0–6.9
7.0–8.9
9.0–
10.9
614,342
—
—
1,075,099
—
—
—
1,382,270
—
606,866
3,064,235
614,342
307,171
916,529
460,757
307,171
—
307,171
455,773
—
—
—
—
153,586
—
153,586
—
153,586
307,171
458,265
—
767,928
151,094
1,535,855
—
916,529
—
755,468
151,094
2,434,941
611,850
153,586
122,495
—
12,330
197,272
12,330
61,648
—
184,943
—
121,295
135,224
135,625
73,777
36,588
61,447
12,330
—
123,095
36,588
—
60,647
12,129
12,330
61,447
—
12,330
—
258,920
49,318
49,118
12,330
73,377
12,330
36,989
12,330
159,083
—
109,765
36,388
255,319
36,788
—
36,989
36,989
—
135,625
—
12,330
—
36,989
—
24,259
86,106
172,613
—
61,247
61,648
12,330
24,459
98,636
24,459
12,330
12,129
—
—
36,989
—
—
—
147,954
36,989
24,459
12,129
24,459
12,129
—
—
171,813
—
48,718
48,518
145,554
—
—
49,318
—
—
36,989
—
—
—
36,989
12,330
84,906
61,047
86,307
12,330
36,588
—
—
12,129
86,307
12,129
—
12,129
—
—
61,648
85,706
—
—
49,318
—
—
12,129
—
—
—
—
12,330
—
12,129
60,647
97,036
—
—
11.0–
12.9
13.0–
14.9
15.0–
16.9
17.0–
18.9
—
—
—
61,648
—
—
—
—
—
24,259
48,718
24,659
—
48,518
24,659
24,659
—
147,954
12,129
—
—
—
12,330
24,659
171,813
—
—
24,659
—
12,330
—
12,330
—
—
—
86,106
—
24,459
12,129
48,518
—
—
—
—
—
—
—
—
12,129
—
—
24,259
12,129
49,318
—
12,129
—
—
—
98,636
—
—
—
—
—
12,330
49,118
—
12,330
—
—
—
—
—
12,330
—
—
36,388
—
12,129
12,129
12,129
—
—
Number of trees
24,659
—
—
—
—
—
24,659
—
—
—
—
—
—
—
—
—
—
—
12,129
—
—
—
—
—
—
—
24,259
—
—
—
—
—
—
12,330
86,307 73,977
—
12,129
—
—
—
—
—
—
—
—
12,330
—
—
12,330
—
—
—
—
—
—
—
—
—
—
24,259
—
—
—
—
—
—
—
—
—
36,788
—
—
12,129
12,129
—
24,259 12,129
12,129 12,129
—
—
—
—
19.0–
20.9
21.0–
22.9
23.0–
24.9
25.0–
26.9
27.0–
28.9
29.0+
—
—
—
—
—
—
12,129
—
—
—
—
—
—
36,588
—
—
—
36,989
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
12,129
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
12,330
—
—
—
12,330
36,989
—
—
—
—
—
—
—
—
—
—
—
—
12,330
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
12,129
—
—
—
—
—
—
12,129
—
—
—
36,989
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
12,129
—
12,330
—
—
—
—
—
—
—
—
—
—
—
—
12,129
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
12,129
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
12,330
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
All
classes
847,803
36,989
12,330
1,531,290
12,330
73,977
48,518
1,641,189
24,659
897,973
3,407,461
1,095,193
405,607
1,184,578
608,511
356,489
61,247
1,133,048
553,209
12,330
84,906
24,259
24,659
362,987
318,967
165,915
12,330
634,436
393,478
544,171
73,177
878,093
187,882
1,572,844
12,330
1,419,038
12,129
974,799
381,553
3,017,755
648,639
153,586
Table 3—Estimated number of live trees on forest land by species and diameter class (continued)
Diameter class (inches)
Species
19
Fagraea ksid
Ficus tinctoria
Flacourtia rukam
Garcinia matudai
Garcinia rumiyo
Garcinia sp.
Gironniera celtidifolia
Glochidion ramiflorum
Glochidion sp.
Gmelina elliptica
Gmelina palawensis
Gmelina sp.
Guettarda speciosa
Gulubia palauensis
Hernandia sonora
Hernandia sp.
Heterospathe elata
Hibiscus tiliaceus
Horsfieldia amklaal
Horsfieldia novo–guineensis
Horsfieldia palauensis
Horsfieldia sp.
Inocarpus fagifer
Intsia bijuga
Lumnitzera littorea
Macaranga carolinensis
Manilkara udoido
Manilkara zapota
Morinda citrifolia
Morinda latibracteata
Morinda pedunculata
Morinda sp.
Mussaenda frondosa
Neonauclea forsteri
Nephelium lappaceum
Osmoxylon oliveri
Osmoxylon sp.
Pandanus aimiriikensis
Pandanus dubius
Pandanus kanehirae
Pandanus palawensis
Pandanus tectorius
Pandamus utiyamai
≤5.0
5.0–6.9
7.0–8.9
—
1,072,607
1,228,684
921,513
2,150,197
307,171
—
1,369,810
153,586
606,866
460,757
—
460,757
—
—
—
614,342
2,610,954
757,960
767,928
2,895,698
614,342
—
151,094
—
4,914,737
—
—
921,513
—
—
—
153,586
460,757
—
153,586
614,342
3,069,219
604,374
153,586
153,586
460,757
—
49,318
—
110,565
36,989
135,425
221,131
24,659
85,506
24,659
60,847
234,261
—
—
97,036
12,129
24,259
61,648
49,318
146,954
86,307
478,850
12,330
12,330
12,129
—
110,565
197,272
24,659
—
61,648
12,330
36,989
—
—
—
24,659
61,648
36,989
181,942
—
—
73,977
—
—
12,129
36,989
12,330
85,706
49,118
12,330
85,506
—
24,259
135,625
24,659
—
—
12,129
—
24,659
49,318
36,788
36,989
208,201
—
—
48,518
—
36,989
36,989
—
24,659
—
—
—
—
—
12,330
—
—
12,330
24,259
49,318
—
24,659
—
9.0–
10.9
61,648
—
—
12,330
49,118
48,718
—
12,129
—
24,259
86,106
12,330
—
—
—
12,129
—
—
—
49,318
159,283
—
—
24,259
12,330
12,129
12,330
12,330
—
—
—
—
—
—
—
—
—
12,330
—
—
—
—
—
11.0–
12.9
13.0–
14.9
15.0–
16.9
17.0–
18.9
24,659
—
12,330
—
36,989
24,659
—
12,330
—
24,259
49,118
12,330
—
—
12,129
12,129
—
—
12,330
—
48,918
—
—
12,129
—
—
—
12,330
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
12,330
—
—
12,330
—
—
—
—
—
24,259
36,989
12,330
—
—
—
—
—
—
36,788
12,330
12,129
—
—
24,259
—
—
12,330
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
Number of trees
24,659
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
24,459 12,129
—
24,459
—
12,330
—
—
—
—
—
—
—
—
—
—
—
—
—
—
12,330 12,330
—
—
—
—
—
—
24,259 24,259
—
—
—
—
12,330 12,330
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
19.0–
20.9
21.0–
22.9
23.0–
24.9
25.0–
26.9
27.0–
28.9
—
—
—
—
—
—
—
—
—
12,330
—
—
—
—
—
—
—
—
—
12,330
12,129
—
—
12,129
—
—
—
12,330
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
12,129
—
—
—
12,330
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
12,129
—
—
—
—
—
—
—
12,129
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
12,330
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
12,330
—
—
—
—
—
12,129
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
12,330
—
29.0+
—
12,129
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
12,330
12,330
24,659
—
—
12,129
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
All
classes
172,613
1,096,866
1,388,568
995,490
2,457,435
650,797
36,989
1,565,282
178,245
825,997
1,027,314
73,977
460,757
97,036
36,388
60,647
700,649
2,709,590
1,003,150
1,002,188
3,852,198
626,672
12,330
381,553
12,330
5,074,420
283,579
73,977
946,172
61,648
12,330
36,989
153,586
460,757
12,330
178,245
675,990
3,130,866
810,575
202,904
153,586
559,393
12,330
20
Table 3—Estimated number of live trees on forest land by species and diameter class (continued)
Diameter class (inches)
Species
Pangium edule
Parinari corymbosum
Parinari laurina
Parinari sp.
Pinanga insignis
Pithecellobium dulce
Pongamia pinnata
Pouteria calcarea
Pouteria obovata
Pouteria sp.
Premna obtusifolia
Pterocarpus indicus
Ptychosperma palauensis
Rhizophora apiculata
Rhizophora mucronata
Rhus taitensis
Rinorea carolinensis
Semecarpus venenosus
Sonneratia alba
Stemonurus ammui
Swietenia macrophylla
Swietenia mahagoni
Symplocos racemosa
Tecoma stans
Terminalia catappa
Theobroma cacao
Timonius subauritus
Tournefortia argentea
Trichospermum ledermannii
Vitex cofassus
Xylocarpus granatum
Unknown 0
Unknown 1
Unknown 2
Unknown 3
Unknown 5
Unknown 11
Unknown, other
Total
≤5.0
—
1,379,778
1,520,904
307,171
9,522,303
453,281
151,094
—
453,281
—
307,171
—
153,586
2,288,831
—
307,171
—
1,689,441
5,836,250
—
153,586
307,171
767,928
153,586
—
—
1,510,936
—
153,586
—
153,586
151,094
307,171
307,171
—
—
—
—
5.0–6.9
—
184,743
282,778
24,659
2,083,686
—
—
36,989
134,424
—
49,318
—
86,307
782,687
242,589
86,307
—
271,049
12,330
—
36,989
49,318
49,318
—
—
12,330
36,388
12,129
36,989
—
61,648
36,989
12,129
—
12,330
24,259
—
12,330
7.0–8.9
12,330
73,777
86,106
—
36,989
12,129
—
—
134,224
12,330
24,659
—
—
401,472
85,506
98,636
12,129
135,224
24,659
12,330
—
12,330
12,330
—
12,330
24,659
24,259
12,129
24,659
12,330
24,659
—
12,330
—
—
36,989
—
—
9.0–
10.9
12,330
36,989
98,436
—
12,330
—
—
—
73,177
—
—
—
—
110,565
12,330
61,648
—
73,177
—
—
12,330
12,330
—
—
24,659
—
12,129
12,330
24,659
—
36,989
—
—
—
—
24,659
12,330
12,330
11.0–
12.9
13.0–
14.9
15.0–
16.9
17.0–
18.9
—
61,648
48,918
—
—
—
—
—
36,388
—
—
—
—
36,788
24,659
61,648
—
49,118
12,330
—
—
—
—
—
12,330
24,659
—
—
12,330
—
12,330
—
—
—
12,330
—
—
—
—
86,307
—
—
—
—
—
—
—
—
—
—
—
36,788
—
61,648
—
12,129
—
—
—
—
—
—
—
—
—
12,330
—
12,330
36,989
—
—
—
—
—
—
—
Number of trees
—
—
12,330 12,330
36,989
—
—
—
—
—
—
—
—
—
—
—
—
12,129
—
—
—
—
12,330
—
—
—
—
—
—
—
24,659 12,330
—
—
12,129
—
12,330
—
12,330 12,330
—
—
—
—
—
—
—
—
—
—
—
—
12,129
—
—
—
—
—
24,659 12,330
—
12,330
—
—
—
—
—
—
—
—
—
—
—
—
—
—
19.0–
20.9
21.0–
22.9
23.0–
24.9
25.0–
26.9
27.0–
28.9
—
12,330
—
—
—
—
—
—
12,330
—
—
—
—
—
—
—
—
—
—
24,659
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
24,659
—
—
—
—
—
—
—
—
—
12,330
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
24,659
—
—
—
—
—
—
—
—
—
—
—
12,330 49,318 12,330
12,129 —
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
12,330
—
—
—
24,659
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
12,330 12,330
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
29.0+
All
classes
—
24,659
49,318 2,008,182
—
2,086,261
—
331,830
—
11,655,307
—
465,410
—
151,094
—
36,989
—
855,954
—
12,330
—
381,148
—
24,659
—
239,892
—
3,657,133
—
365,084
—
714,045
—
12,129
12,330 2,266,927
36,989 5,959,545
—
61,648
—
202,904
—
381,148
—
829,575
—
153,586
—
49,318
—
61,648
—
1,595,842
—
48,918
—
252,222
—
110,966
—
338,528
—
188,082
—
331,630
—
307,171
—
24,659
—
85,906
—
12,330
12,330
36,989
76,110,228 10,058,255 4,047,132 2,219,238 1,558,645 822,076 551,827 318,767 220,731 160,084 122,295 135,024 73,777 196,872 96,594,950
Palau’s Forest Resources, 2003
70,000
57,612
60,000
Area (acres)
50,000
Volcanic
Limestone
40,000
30,000
20,000
10,000
0
14,202 12,091
6,272
6,511
Less than 5
5–10.9
Stand size class (inches)
11–19.9
Figure 6—The trees that characterize volcanic forests tend to be somewhat small, in the 5- to
11-inch category. Forested stands on limestone soils tend to be characterized by larger trees in
the 11- to 20-inch category.
60
Trees (millions)
50
Number of trees by size class
Total trees in all classes: 94,598,338
40
30
20
10
1.
0–
2
3. .9
0–
4
5. .9
0–
6
7. .9
0–
9. 8.9
0–
11 10
.0 .9
–
13 12.
.0 9
–
15 14
.0 .9
–
17 16
.0 .9
–
19 18.
.0 9
–
21 20.
.0 9
–
23 22
.0 .9
–
25 24.
.0 9
–
27 26.
.0 9
–2
8.
9
29
.0
+
0
Diameter (inches)
Figure 7—Small trees are very common in Palau, indicating regeneration is abundant.
21
RESOURCE BULLETIN PNW-RB-252
Number of trees (millions)
7
6
Number of trees
by height class
5
(>5 inches diameter)
4
3
2
1
+
9
10
0
–9
90
9
70
–7
9
80
–8
9
–6
9
60
–5
9
50
–4
9
40
–3
30
10
–1
9
20
–2
9
<1
0
0
Height (feet)
90
80
Volume by size class
70
Total volume in all classes: 268,020,715
60
50
40
30
20
10
5.
0–
9
40
+
0
.9
10
.0
–1
4.
9
15
.0
–1
9.
9
20
.0
–2
4.
9
25
.0
–2
9.
9
30
.0
–3
4.
9
35
.0
–3
9.
9
Gross volume (million cubic feet)
Figure 8—For trees greater than or equal to 5 inches in diameter, the most common heights attained
range from 30 to 50 feet tall.
Diameter (inches)
Figure 9—As with numbers of trees, gross volume of wood tends to be concentrated in the smaller
diameter classes. However, many larger diameter trees contribute to the substantial volume in those
size classes.
22
Palau’s Forest Resources, 2003
Table 4—Estimated gross volume of all live trees on forest land by forest-type group and
diameter class
Diameter class (inches)
Forest-type group
Less than 5
5–10.9
11–19.9
Limestone forest
Volcanic/ravine forest
6,248,751
28,116,999
28,309,959
62,596,123
Cubic feet
28,665,545
60,913,733
19,013,470
68,521,890
82,237,724
220,148,745
34,365,749
90,906,081
89,579,278
87,535,360
302,386,469
Total
20+ All sizes
Table 5—Estimated net volume of all live trees ≥5 inches in diameter on
forest land by forest-type group and diameter class
Diameter class (inches)
Forest-type group
Limestone forest
Volcanic/ravine forest
11–19.9
20+ All sizes
28,285,444
62,311,497
Cubic feet
28,570,500
18,577,815
60,297,635
67,289,502
75,433,759
189,898,634
90,596,941
88,868,135
265,332,393
85,867,317
1,400
1,200
Biomass by size class
1,000
Biomass total, all classes: 4,686,793
800
600
400
200
5.
0–
9
40
+
0
.9
10
.0
–1
4.
9
15
.0
–1
9.
9
20
.0
–2
4.
9
25
.0
–2
9.
9
30
.0
–3
4.
9
35
.0
–3
9.
9
Stem biomass (thousand tons)
Total
5–10.9
Diameter (inches)
Figure 10—Biomass is also concentrated in the smaller size classes.
23
24
Table 6—Estimated gross volume of all live trees on forest land by species and diameter class
Diameter class (inches)
Species
5.0–6.9
358,196
Aglaia palauensis
—
Allophylus ternatus
29,280
Allophylus timorensis
735,731
Alphitonia carolinensis
62,771
Annona reticulata
211,184
Areca catechu
—
Artocarpus mariannensis
577,119
Astronidium palauense
—
Avicennia marina
453,193
Badusa palauensis
452,159
Barringtonia racemosa
524,400
Bruguiera gymnorrhiza
243,769
Buchanania palawensis
188,139
Calophyllum inophyllum
204,921
Calophyllum pelewense
63,170
Calophyllum soulattri
—
Calophyllum sp.
Campnosperma brevipetiolata 410,952
116,651
Canarium hirsutum
—
Casearia cauliflora
300,526
Casearia sp.
33,773
Casuarina equisetifolia
50,830
Cerbera floribunda
261,427
Cerbera manghas
—
Cocos nucifera
29,882
Commersonia bartramia
—
Cordia micronesica
683,380
Cyathea lunulata
128,287
Diospyros ferrea
187,930
Diospyros sp.
34,597
Dodonaea viscosa
204,143
Dracaena multiflora
47,105
Drypetes nitida
64,752
Dysoxylum sp.
64,508
Elaeocarpus graeffei
662,676
Elaeocarpus joga
—
Erythrina fusca
383,104
Eugenia cumini
127,922
Eugenia javanica
1,003,419
Eugenia reinwardtiana
130,011
Eugenia sp.
161,826
Fagraea ksid
—
Ficus sp.
—
Ficus tinctoria
7.0–8.9
217,203
206,199
—
1,129,350
—
80,981
—
208,231
—
211,682
527,080
1,038,683
—
500,540
498,086
79,559
164,982
750,845
119,701
157,802
118,182
—
—
272,907
—
—
—
708,128
256,014
277,568
67,158
115,524
74,774
—
—
1,399,992
—
338,074
369,502
1,093,777
—
—
—
56,385
9.0–
10.9
448,937
—
—
467,218
—
—
—
364,270
114,276
816,673
711,656
871,613
140,678
392,480
—
—
192,860
973,757
142,942
—
207,941
—
—
719,166
1,364,708
—
—
306,007
—
—
163,789
—
—
—
—
95,607
—
160,248
677,261
1,425,442
—
499,547
—
—
11.0–
12.9
13.0–
14.9
15.0–
16.9
—
—
—
1,269,881
—
—
—
—
—
379,532
1,053,700
397,703
—
704,449
337,712
338,061
—
2,465,508
195,799
—
—
—
143,752
529,306
4,923,463
—
—
277,547
—
251,528
—
147,157
—
—
—
1,623,421
—
380,749
190,441
930,288
—
481,374
—
—
—
—
—
—
—
—
440,417
—
—
578,607
229,549
852,655
—
194,770
—
—
—
2,491,979
—
—
—
—
—
267,966
1,481,204
—
312,315
—
—
—
—
—
251,142
—
—
1,376,416
—
298,384
297,325
382,084
—
277,505
—
—
759,169
—
—
834,761
—
—
—
—
—
608,341
—
—
—
748,863
—
—
—
3,277,299
—
—
—
—
—
294,836
—
—
—
—
—
—
846,599
—
—
—
—
1,568,153
—
400,104
740,797
560,575
—
822,261
—
—
17.0–
18.9
19.0–
20.9
Cubic feet
—
—
—
—
—
—
—
—
—
—
—
—
—
635,097
—
—
—
—
—
—
—
—
—
—
—
—
—
1,760,060
—
—
—
—
309,745
—
4,050,260 1,937,832
497,877
—
—
—
—
—
—
—
—
—
—
—
647,213
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
600,183
—
—
—
497,380
426,207
616,284
—
—
—
—
—
—
409,933
—
—
21.0–
22.9
23.0–
24.9
25.0–
26.9
27.0–
28.9
29.0+
—
—
—
—
—
—
—
—
—
—
—
—
924,553
—
—
—
1,243,385
3,038,783
—
—
—
—
—
—
—
—
—
—
—
—
530,228
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
1,278,815
—
—
—
—
—
—
947,598
—
—
—
3,494,230
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
2,134,102
—
1,308,417
—
—
—
—
—
—
—
—
—
—
—
—
1,403,132
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
1,092,791
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
1,857,843
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
2,606,279
All
classes
1,783,505
206,199
29,280
4,436,940
62,771
292,165
4,488,431
1,149,620
1,422,693
3,048,028
2,974,144
5,542,897
1,308,999
5,436,901
1,040,719
480,790
1,910,972
22,891,446
1,072,970
157,802
626,648
1,436,905
194,582
2,345,608
8,416,588
29,882
312,315
1,975,061
384,300
717,026
1,642,371
466,823
373,021
64,752
64,508
6,726,266
600,183
1,960,664
4,419,626
6,011,868
130,011
2,242,513
409,933
2,662,664
Table 6—Estimated gross volume of all live trees on forest land by species and diameter class (continued)
Diameter class (inches)
Species
25
Flacourtia rukam
Garcinia matudai
Garcinia rumiyo
Garcinia sp.
Gironniera celtidifolia
Glochidion ramiflorum
Glochidion sp.
Gmelina elliptica
Gmelina palawensis
Gmelina sp.
Gulubia palauensis
Hernandia sonora
Hernandia sp.
Heterospathe elata
Hibiscus tiliaceus
Horsfieldia amklaal
Horsfieldia novo-guineensis
Horsfieldia palauensis
Horsfieldia sp.
Inocarpus fagifer
Intsia bijuga
Lumnitzera littorea
Macaranga carolinensis
Manilkara udoido
Manilkara zapota
Morinda citrifolia
Morinda latibracteata
Morinda pedunculata
Morinda sp.
Nephelium lappaceum
Osmoxylon oliveri
Osmoxylon sp.
Pandanus aimiriikensis
Pandanus dubius
Pandanus kanehirae
Pandanus tectorius
Pandanus utiyamai
Pangium edule
Parinari corymbosum
Parinari laurina
Parinari sp.
Pinanga insignis
Pithecellobium dulce
Pouteria calcarea
5.0–6.9
7.0–8.9
399,756
181,521
547,736
937,863
89,179
296,385
93,117
218,166
860,819
—
518,759
48,678
72,835
223,139
157,229
604,676
303,272
1,795,603
61,419
29,390
60,415
—
328,807
753,108
95,965
—
211,608
81,626
127,267
—
65,896
145,875
136,228
677,136
—
261,072
—
—
689,431
1,056,482
66,714
7,832,438
—
160,981
205,465
80,400
734,850
459,661
172,200
533,580
—
159,556
888,819
275,888
—
93,646
—
181,631
191,147
248,982
254,896
1,549,305
—
—
420,363
—
186,047
207,350
—
142,104
—
—
—
100,828
—
—
51,506
220,116
332,031
188,207
—
73,623
506,454
521,650
—
303,291
80,161
—
9.0–
10.9
—
155,242
507,022
605,835
—
139,993
—
363,533
771,909
190,681
—
—
120,735
—
—
—
744,724
1,962,502
—
—
256,073
127,232
167,974
226,930
119,687
—
—
—
—
—
—
—
84,627
—
—
—
—
163,712
431,678
925,184
—
133,263
—
—
11.0–
12.9
13.0–
14.9
15.0–
16.9
146,034
—
730,739
579,278
—
231,111
—
401,804
732,695
268,382
—
227,398
144,215
—
—
270,510
—
870,606
—
—
176,722
—
—
—
177,080
—
—
—
—
—
—
—
—
—
—
—
—
—
1,097,576
962,513
—
—
—
—
—
307,851
—
—
—
—
—
534,904
1,121,009
159,607
—
—
—
—
—
1,020,728
344,493
242,883
—
—
609,515
—
—
225,960
—
—
—
—
—
—
—
—
—
—
—
—
—
—
1,990,397
—
—
—
—
—
—
—
—
—
—
—
—
701,063
—
—
—
—
—
—
—
—
396,646
—
—
—
1,153,528
—
—
288,213
—
—
—
—
—
—
—
—
—
—
—
—
—
—
421,904
1,115,534
—
—
—
—
17.0–
18.9
19.0–
20.9
Cubic feet
—
—
—
—
—
—
—
—
—
—
—
—
—
—
694,331
513,192
673,159
—
420,704
—
—
—
—
—
—
—
—
—
—
—
—
—
806,216
930,642
—
856,766
—
—
—
—
1,228,373
633,825
—
—
—
—
383,995
—
—
328,616
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
852,296
607,489
—
—
—
—
—
—
—
—
—
—
21.0–
22.9
23.0–
24.9
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
742,335
—
—
—
575,215
—
—
—
—
—
—
—
—
—
—
—
—
—
1,822,127
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
1,376,732
—
—
—
—
—
—
—
1,089,139
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
1,386,894
1,399,150
—
—
—
—
25.0–
26.9
27.0–
28.9
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
897,498
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
1,138,744
—
—
—
—
—
1,507,134
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
1,050,209
—
—
—
3,444,684 1,289,904
—
—
—
—
—
—
—
—
—
—
29.0+
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
2,995,219
6,929,268
5,239,828
—
—
1,462,131
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
7,877,115
—
—
—
—
—
All
classes
751,255
725,013
2,520,347
2,582,637
261,379
1,201,069
93,117
4,484,048
5,048,410
1,315,262
518,759
369,722
1,714,517
404,770
348,375
5,140,116
10,710,158
13,656,236
61,419
29,390
9,339,552
127,232
682,828
2,085,556
1,296,562
142,104
211,608
81,626
127,267
100,828
65,896
145,875
272,360
897,251
332,031
449,279
1,050,209
237,335
22,417,949
5,980,513
66,714
8,268,992
80,161
160,981
26
Table 6—Estimated gross volume of all live trees on forest land by species and diameter class (continued)
Diameter class (inches)
Species
Pouteria obovata
Pouteria sp.
Premna obtusifolia
Pterocarpus indicus
Ptychosperma palauensis
Rhizophora apiculata
Rhizophora mucronata
Rhus taitensis
Rinorea carolinensis
Semecarpus venenosus
Sonneratia alba
Stemonurus ammui
Swietenia macrophylla
Swietenia mahagoni
Symplocos racemosa
Terminalia catappa
Theobroma cacao
Timonius subauritus
Tournefortia argentea
Trichospermum ledermannii
Vitex cofassus
Xylocarpus granatum
Unknown 0
Unknown 1
Unknown 3
Unknown 5
Unknown 11
Unknown, other
Total
5.0–6.9
541,147
—
127,669
—
314,678
3,089,759
815,800
288,555
—
1,155,137
23,568
—
175,805
179,811
128,478
—
30,258
168,555
22,145
129,573
—
178,267
120,479
35,180
44,577
67,712
—
50,997
7.0–8.9
9.0–
10.9
11.0–
12.9
13.0–
14.9
15.0–
16.9
1,054,853
59,315
119,095
—
—
864,486
—
—
—
—
712,852
—
—
—
—
—
—
—
—
—
—
—
—
229,537
—
Cubic feet
595,227
392,699
—
—
—
—
—
—
—
—
—
1,461,139
—
312,069
—
—
—
—
—
—
—
—
143,626
—
319,190
554,708
—
—
—
—
—
—
495,846
—
526,363
538,634
633,032
—
—
—
—
—
438,429
—
—
714,086
—
—
—
—
—
—
—
560,851
—
—
—
808,378
—
—
—
—
—
—
—
—
435,761
239,527
—
—
—
—
—
—
2,545,438
758,392
725,964
44,758
852,343
169,976
70,618
—
71,296
96,128
165,490
187,894
187,252
44,889
288,139
91,031
113,859
—
48,232
—
235,500
—
—
1,320,834
183,142
586,929
—
954,517
—
—
151,802
163,613
—
340,579
—
131,543
116,849
387,762
—
368,179
—
—
—
210,219
126,165
140,256
612,144
507,898
1,176,660
—
891,534
149,403
—
—
—
—
298,932
399,693
—
—
262,220
—
178,624
—
—
184,062
—
—
—
882,643
—
—
17.0–
18.9
—
—
19.0–
20.9
—
—
—
—
—
—
1,703,686
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
21.0–
22.9
23.0–
24.9
—
—
—
488,213
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
1,255,579
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
1,024,803
—
—
—
—
—
—
—
25.0–
26.9
—
—
—
—
—
—
—
27.0–
28.9
29.0+
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
1,367,032
—
—
2,270,776
—
—
—
—
—
—
—
—
—
—
—
—
—
—
924,646
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
1,364,929
8,351,476
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
1,440,229
All
classes
4,161,263
59,315
246,764
717,750
314,678
8,450,819
2,265,232
5,295,943
44,758
7,423,924
11,503,833
3,215,714
327,606
414,720
224,606
805,001
617,845
925,779
327,509
1,067,694
4,765,096
1,633,164
120,479
83,412
228,639
513,431
126,165
1,631,482
37,070,470 28,333,126 25,502,485 29,412,054 19,963,042 19,114,573 14,917,757 11,136,046 10,620,417 11,997,362 12,725,013 7,104,057 40,124,318 268,020,719
Table 7—Estimated aboveground dry stem weight of all live trees on forest land by species and diameter class
Diameter class (inches)
Species
27
Aglaia palauensis
Allophylus ternatus
Allophylus timorensis
Alphitonia carolinensis
Annona reticulata
Areca catechu
Artocarpus mariannensis
Astronidium palauense
Avicennia marina
Badusa palauensis
Barringtonia racemosa
Bruguiera gymnorrhiza
Buchanania palawensis
Calophyllum inophyllum
Calophyllum pelewense
Calophyllum soulattri
Calophyllum sp.
Campnosperma brevipetiolata
Canarium hirsutum
Casearia cauliflora
Casearia sp.
Casuarina equisetifolia
Cerbera floribunda
Cerbera manghas
Cocos nucifera
Commersonia bartramia
Cordia micronesica
Cyathea lunulata
Diospyros ferrea
Diospyros sp.
Dodonaea viscosa
Dracaena multiflora
Drypetes nitida
Dysoxylum sp.
Elaeocarpus graeffei
Elaeocarpus joga
Erythrina fusca
Eugenia cumini
Eugenia javanica
Eugenia reinwardtiana
Eugenia sp.
Fagraea ksid
Ficus sp.
Ficus tinctoria
5.0–6.9
7.0–8.9
9.0–
10.9
5,722
—
468
11,753
1,003
3,374
—
9,219
—
7,240
7,223
8,377
3,894
3,426
3,274
1,009
—
6,565
1,491
—
5,953
896
812
4,176
—
477
—
10,917
2,869
4,203
553
3,261
753
1,034
1,031
10,586
—
7,955
2,656
20,836
2,700
3,775
—
—
3,470
3,294
—
18,041
—
1,294
—
3,326
—
3,382
8,420
16,593
—
9,115
7,957
1,271
3,426
11,995
1,530
2,521
2,341
—
—
4,360
—
—
—
11,312
5,726
6,208
1,073
1,845
1,195
—
—
22,365
—
7,020
7,673
22,712
—
—
—
703
7,172
—
—
7,464
—
—
—
5,819
1,826
13,046
11,369
13,924
2,247
7,147
—
—
4,005
15,556
1,827
—
4,119
—
—
11,489
21,801
—
—
4,888
—
—
2,617
—
—
—
—
1,527
—
3,328
14,063
29,599
—
11,652
—
—
11.0–
12.9
13.0–
14.9
15.0–
16.9
17.0–
18.9
19.0–
20.9
21.0–
22.9
23.0–
24.9
25.0–
26.9
27.0–
28.9
29.0+
All
classes
—
—
—
20,286
—
—
—
—
—
6,063
16,833
6,353
—
12,828
5,395
5,401
—
39,386
2,502
—
—
—
2,296
8,456
78,652
—
—
4,434
—
5,625
—
2,351
—
—
—
25,934
—
7,906
3,955
19,317
—
11,228
—
—
—
—
—
—
—
—
7,036
—
—
9,243
3,667
13,621
—
3,547
—
—
—
39,809
—
—
—
—
—
4,281
23,662
—
5,287
—
—
—
—
—
4,012
—
—
21,988
—
6,196
6,174
7,934
—
6,473
—
—
12,128
—
—
13,335
—
—
—
—
—
9,718
—
—
—
13,637
—
—
—
52,355
—
—
—
—
—
4,710
—
—
—
—
—
—
13,524
—
—
—
—
25,051
—
8,308
15,383
11,640
—
19,179
—
—
Tons
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
6,432
64,703
6,363
—
—
—
—
—
10,339
—
—
—
—
—
—
—
—
—
—
—
4,792
—
10,328
12,797
—
—
—
—
—
—
—
—
—
—
10,146
—
—
—
—
—
—
32,051
—
—
—
30,957
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
8,850
—
—
—
4,190
—
—
—
—
—
—
—
—
—
—
—
—
—
14,770
—
—
—
25,819
48,545
—
—
—
—
—
—
—
—
—
—
—
—
8,470
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
20,429
—
—
—
—
—
—
17,256
—
—
—
55,820
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
34,092
—
20,902
—
—
—
—
—
—
—
—
—
—
—
—
37,211
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
22,692
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
29,679
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
32,474
28,491
3,294
468
70,880
1,003
4,667
71,703
18,365
22,728
48,692
47,512
88,548
20,911
99,006
16,625
7,681
39,681
365,691
13,713
2,521
12,414
38,107
3,108
37,471
134,455
477
5,287
31,552
8,595
16,036
26,237
7,458
5,959
1,034
1,031
107,452
4,792
40,713
91,774
124,836
2,700
52,307
4,190
33,177
28
Table 7—Estimated aboveground dry stem weight of all live trees on forest land by species and diameter class (continued)
Diameter class (inches)
Species
5.0–6.9
7.0–8.9
9.0–
10.9
Flacourtia rukam
Garcinia matudai
Garcinia rumiyo
Garcinia sp.
Gironniera celtidifolia
Glochidion ramiflorum
Glochidion sp.
Gmelina elliptica
Gmelina palawensis
Gmelina sp.
Gulubia palauensis
Hernandia sonora
Hernandia sp.
Heterospathe elata
Hibiscus tiliaceus
Horsfieldia amklaal
Horsfieldia novo-guineensis
Horsfieldia palauensis
Horsfieldia sp.
Inocarpus fagifer
Intsia bijuga
Lumnitzera littorea
Macaranga carolinensis
Manilkara udoido
Manilkara zapota
Morinda citrifolia
Morinda latibracteata
Morinda pedunculata
Morinda sp.
Nephelium lappaceum
Osmoxylon oliveri
Osmoxylon sp.
Pandanus aimiriikensis
Pandanus dubius
Pandanus kanehirae
Pandanus tectorius
Pandanus utiyamai
Pangium edule
Parinari corymbosum
Parinari laurina
Parinari sp.
Pinanga insignis
Pithecellobium dulce
Pouteria calcarea
6,386
4,349
13,124
22,471
1,425
4,735
1,488
3,485
13,752
—
8,287
451
1,164
3,565
2,863
9,660
4,845
28,685
981
470
1,177
—
5,253
12,031
1,533
—
3,380
1,304
2,033
—
1,053
2,330
2,176
10,817
—
4,171
—
—
16,739
22,952
1,449
125,123
—
2,572
3,282
1,926
17,607
11,013
2,751
8,524
—
2,549
14,199
4,407
—
868
—
2,902
3,481
3,977
4,072
24,750
—
—
8,193
—
2,972
3,312
—
2,270
—
—
—
1,611
—
—
823
3,516
5,304
3,007
—
1,176
12,297
11,333
—
4,845
1,281
—
—
3,720
12,148
14,516
—
2,236
—
5,807
12,331
3,046
—
—
1,929
—
—
—
11,897
31,351
—
—
4,991
2,033
2,683
3,625
1,912
—
—
—
—
—
—
—
1,352
—
—
—
—
2,615
10,481
20,100
—
2,129
—
—
11.0–
12.9
13.0–
14.9
15.0–
16.9
17.0–
18.9
19.0–
20.9
21.0–
22.9
23.0–
24.9
25.0–
26.9
27.0–
28.9
29.0+
All
classes
2,333
—
17,509
13,880
—
3,692
—
6,419
11,705
4,287
—
2,107
2,304
—
—
4,321
—
13,908
—
—
3,444
—
—
—
2,829
—
—
—
—
—
—
—
—
—
—
—
—
—
26,649
20,911
—
—
—
—
—
7,376
—
—
—
—
—
8,545
17,908
2,550
—
—
—
—
—
16,306
5,503
3,880
—
—
11,879
—
—
3,610
—
—
—
—
—
—
—
—
—
—
—
—
—
—
48,327
—
—
—
—
—
—
—
—
—
—
—
—
11,199
—
—
—
—
—
—
—
—
6,336
—
—
—
22,482
—
—
4,604
—
—
—
—
—
—
—
—
—
—
—
—
—
—
10,244
24,235
—
—
—
—
Tons
—
—
—
—
—
—
—
11,092
10,754
6,721
—
—
—
—
—
—
12,879
—
—
—
23,941
—
—
6,134
—
—
—
—
—
—
—
—
—
—
—
—
—
—
20,694
—
—
—
—
—
—
—
—
—
—
—
—
8,198
—
—
—
—
—
—
—
—
14,867
13,687
—
—
12,353
—
—
—
5,250
—
—
—
—
—
—
—
—
—
—
—
—
—
14,750
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
14,468
—
—
—
9,189
—
—
—
—
—
—
—
—
—
—
—
—
—
44,241
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
21,993
—
—
—
—
—
—
—
21,227
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
33,674
30,397
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
16,777
—
83,637
—
—
—
—
—
—
—
—
—
—
—
—
14,338
—
—
—
—
—
—
—
—
—
18,191
—
—
29,374
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
31,319
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
47,849
110,695
83,706
—
—
28,497
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
191,256
—
—
—
—
—
12,001
17,371
60,388
61,880
4,176
19,187
1,488
71,633
80,648
21,011
8,287
3,425
27,389
6,466
6,344
82,113
171,095
218,158
981
470
182,028
2,033
10,908
33,317
20,713
2,270
3,380
1,304
2,033
1,611
1,053
2,330
4,351
14,334
5,304
7,177
16,777
3,791
544,308
129,927
1,449
132,097
1,281
2,572
Table 7—Estimated aboveground dry stem weight of all live trees on forest land by species and diameter class (continued)
Diameter class (inches)
Species
Pouteria obovata
Pouteria sp.
Premna obtusifolia
Pterocarpus indicus
Ptychosperma palauensis
Rhizophora apiculata
Rhizophora mucronata
Rhus taitensis
Rinorea carolinensis
Semecarpus venenosus
Sonneratia alba
Stemonurus ammui
Swietenia macrophylla
Swietenia mahagoni
Symplocos racemosa
Terminalia catappa
Theobroma cacao
Timonius subauritus
Tournefortia argentea
Trichospermum ledermannii
Vitex cofassus
Xylocarpus granatum
Unknown 0
Unknown 1
Unknown 3
Unknown 5
Unknown 11
Unknown, other
Total
5.0–6.9
7.0–8.9
9.0–
10.9
11.0–
12.9
13.0–
14.9
15.0–
16.9
17.0–
18.9
8,645
—
2,040
—
5,027
49,359
13,032
4,610
—
18,453
376
—
2,358
3,505
2,052
—
483
2,693
354
2,070
—
2,848
1,925
562
712
1,082
—
815
16,851
1,384
1,903
—
—
40,663
12,115
11,597
715
13,616
2,715
1,128
—
1,390
1,536
3,119
3,002
2,991
717
4,603
1,454
1,819
—
771
—
3,762
—
—
13,810
—
—
—
—
21,100
2,926
9,376
—
15,248
—
—
2,036
3,189
—
6,420
—
2,101
1,867
6,195
—
5,882
—
—
—
3,358
2,015
2,241
11,388
—
—
—
—
9,779
8,114
18,797
—
14,242
2,387
—
—
—
—
5,635
6,385
—
—
4,189
—
2,854
—
—
2,940
—
—
—
—
—
—
—
—
14,100
—
23,342
—
4,985
—
—
—
—
—
—
—
—
2,294
—
5,099
8,861
—
—
—
—
—
—
—
—
—
3,814
—
—
—
7,921
—
8,409
8,605
10,113
—
—
—
—
—
7,004
—
—
11,408
—
—
—
—
—
—
—
630,759
486,266
445,152
508,209
347,497
335,342
Tons
9,509
6,273
—
—
—
—
—
—
—
—
—
—
—
—
8,960
—
—
—
—
—
—
—
12,914
27,216
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
6,961
—
3,826
—
—
—
—
—
—
—
—
—
—
—
—
—
250,139
19.0–
20.9
188,788
21.0–
22.9
23.0–
24.9
25.0–
26.9
27.0–
28.9
29.0+
All
classes
—
—
—
8,112
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
20,058
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
16,371
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
21,838
—
—
—
—
—
—
—
—
—
—
14,771
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
36,276
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
21,805
133,415
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
23,008
66,476
1,384
3,942
11,925
5,027
135,002
36,187
84,603
715
118,597
183,774
51,371
4,395
8,083
3,588
15,174
9,870
14,789
5,232
17,056
76,122
26,090
1,925
1,333
3,653
8,202
2,015
26,063
193,672
217,167
251,921
129,498
702,384
4,686,793
29
30
Table 8—Estimated carbon mass of all live trees on forest land by species and diameter class
Diameter class (inches)
Species
5.0–6.9
7.0–8.9
9.0–
10.9
Aglaia palauensis
Allophylus ternatus
Allophylus timorensis
Alphitonia carolinensis
Annona reticulata
Areca catechu
Artocarpus mariannensis
Astronidium palauense
Avicennia marina
Badusa palauensis
Barringtonia racemosa
Bruguiera gymnorrhiza
Buchanania palawensis
Calophyllum inophyllum
Calophyllum pelewense
Calophyllum soulattri
Calophyllum sp.
Campnosperma brevipetiolata
Canarium hirsutum
Casearia cauliflora
Casearia sp.
Casuarina equisetifolia
Cerbera floribunda
Cerbera manghas
Cocos nucifera
Commersonia bartramia
Cordia micronesica
Cyathea lunulata
Diospyros ferrea
Diospyros sp.
Dodonaea viscosa
Dracaena multiflora
Drypetes nitida
Dysoxylum sp.
Elaeocarpus graeffei
Elaeocarpus joga
Erythrina fusca
Eugenia cumini
Eugenia javanica
Eugenia reinwardtiana
Eugenia sp.
Fagraea ksid
Ficus sp.
Ficus tinctoria
2,804
—
229
5,759
491
1,653
—
4,518
—
3,547
3,539
4,105
1,908
1,679
1,604
494
—
3,217
730
—
2,917
439
398
2,046
—
234
—
5,349
1,406
2,060
271
1,598
369
507
505
5,187
—
3,898
1,302
10,210
1,323
1,850
—
—
1,700
1,614
—
8,840
—
634
—
1,630
—
1,657
4,126
8,131
—
4,466
3,899
623
1,679
5,877
750
1,235
1,147
—
—
2,136
—
—
—
5,543
2,806
3,042
526
904
585
—
—
10,959
—
3,440
3,760
11,129
—
—
—
344
3,514
—
—
3,657
—
—
—
2,851
895
6,393
5,571
6,823
1,101
3,502
—
—
1,962
7,622
895
—
2,018
—
—
5,629
10,683
—
—
2,395
—
—
1,282
—
—
—
—
748
—
1,631
6,891
14,504
—
5,709
—
—
11.0–
12.9
13.0–
14.9
15.0–
16.9
17.0–
18.9
19.0–
20.9
—
—
—
9,940
—
—
—
—
—
2,971
8,248
3,113
—
6,286
2,644
2,646
—
19,299
1,226
—
—
—
1,125
4,143
38,540
—
—
2,173
—
2,756
—
1,152
—
—
—
12,708
—
3,874
1,938
9,466
—
5,502
—
—
—
—
—
—
—
—
3,447
—
—
4,529
1,797
6,674
—
1,738
—
—
—
19,507
—
—
—
—
—
2,098
11,595
—
2,591
—
—
—
—
—
1,966
—
—
10,774
—
3,036
3,025
3,888
—
3,172
—
—
5,943
—
—
6,534
—
—
—
—
—
4,762
—
—
—
6,682
—
—
—
25,654
—
—
—
—
—
2,308
—
—
—
—
—
—
6,627
—
—
—
—
12,275
—
4,071
7,538
5,704
—
9,398
—
—
Tons
—
—
—
—
—
—
—
—
—
—
—
—
—
4,971
—
—
—
—
—
—
—
—
—
—
—
—
—
15,705
—
—
—
—
3,152
—
31,704
15,169
3,118
—
—
—
—
—
—
—
—
—
—
—
5,066
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
2,348
—
—
—
5,061
4,337
6,271
—
—
—
—
—
—
2,053
—
—
21.0–
22.9
23.0–
24.9
25.0–
26.9
27.0–
28.9
29.0+
All
classes
—
—
—
—
—
—
—
—
—
—
—
—
7,237
—
—
—
12,651
23,787
—
—
—
—
—
—
—
—
—
—
—
—
4,150
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
10,010
—
—
—
—
—
—
8,455
—
—
—
27,352
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
16,705
—
10,242
—
—
—
—
—
—
—
—
—
—
—
—
18,233
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
11,119
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
14,543
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
15,912
13,961
1,614
229
34,731
491
2,287
35,134
8,999
11,136
23,859
23,281
43,388
10,247
48,513
8,146
3,764
19,444
179,189
6,719
1,235
6,083
18,672
1,523
18,361
65,883
234
2,591
15,460
4,211
7,858
12,856
3,654
2,920
507
505
52,652
2,348
19,949
44,969
61,170
1,323
25,630
2,053
16,257
Table 8—Estimated carbon mass of all live trees on forest land by species and diameter class (continued)
Diameter class (inches)
31
Species
5.0–6.9
7.0–8.9
9.0–
10.9
Flacourtia rukam
Garcinia matudai
Garcinia rumiyo
Garcinia sp.
Gironniera celtidifolia
Glochidion ramiflorum
Glochidion sp.
Gmelina elliptica
Gmelina palawensis
Gmelina sp.
Gulubia palauensis
Hernandia sonora
Hernandia sp.
Heterospathe elata
Hibiscus tiliaceus
Horsfieldia amklaal
Horsfieldia novo-guineensis
Horsfieldia palauensis
Horsfieldia sp.
Inocarpus fagifer
Intsia bijuga
Lumnitzera littorea
Macaranga carolinensis
Manilkara udoido
Manilkara zapota
Morinda citrifolia
Morinda latibracteata
Morinda pedunculata
Morinda sp.
Nephelium lappaceum
Osmoxylon oliveri
Osmoxylon sp.
Pandanus aimiriikensis
Pandanus dubius
Pandanus kanehirae
Pandanus tectorius
Pandanus utiyamai
Pangium edule
Parinari corymbosum
Parinari laurina
Parinari sp.
Pinanga insignis
Pithecellobium dulce
Pouteria calcarea
3,129
2,131
6,431
11,011
698
2,320
729
1,708
6,738
—
4,061
221
570
1,747
1,403
4,733
2,374
14,056
481
230
577
—
2,574
5,895
751
—
1,656
639
996
—
516
1,142
1,066
5,300
—
2,044
—
—
8,202
11,247
710
61,310
—
1,260
1,608
944
8,627
5,397
1,348
4,177
—
1,249
6,957
2,160
—
425
—
1,422
1,706
1,949
1,995
12,128
—
—
4,015
—
1,456
1,623
—
1,112
—
—
—
789
—
—
403
1,723
2,599
1,473
—
576
6,025
5,553
—
2,374
627
—
—
1,823
5,953
7,113
—
1,096
—
2,846
6,042
1,493
—
—
945
—
—
—
5,830
15,362
—
—
2,446
996
1,315
1,776
937
—
—
—
—
—
—
—
662
—
—
—
—
1,282
5,136
9,849
—
1,043
—
—
11.0–
12.9
13.0–
14.9
15.0–
16.9
17.0–
18.9
1,143
—
8,579
6,801
—
1,809
—
3,145
5,735
2,101
—
1,032
1,129
—
—
2,117
—
6,815
—
—
1,688
—
—
—
1,386
—
—
—
—
—
—
—
—
—
—
—
—
—
13,058
10,246
—
—
—
—
—
3,614
—
—
—
—
—
4,187
8,775
1,249
—
—
—
—
—
7,990
2,697
1,901
—
—
5,821
—
—
1,769
—
—
—
—
—
—
—
—
—
—
—
—
—
—
23,680
—
—
—
—
—
—
—
—
—
—
—
—
5,488
—
—
—
—
—
—
—
—
3,105
—
—
—
11,016
—
—
2,256
—
—
—
—
—
—
—
—
—
—
—
—
—
—
5,019
11,875
—
—
—
—
Tons
—
—
—
—
—
—
—
5,435
5,269
3,293
—
—
—
—
—
—
6,311
—
—
—
11,731
—
—
3,006
—
—
—
—
—
—
—
—
—
—
—
—
—
—
10,140
—
—
—
—
—
19.0–
20.9
—
—
—
—
—
—
—
4,017
—
—
—
—
—
—
—
—
7,285
6,707
—
—
6,053
—
—
—
2,572
—
—
—
—
—
—
—
—
—
—
—
—
—
7,227
—
—
—
—
—
21.0–
22.9
23.0–
24.9
25.0–
26.9
27.0–
28.9
29.0+
All
classes
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
7,089
—
—
—
4,503
—
—
—
—
—
—
—
—
—
—
—
—
—
21,678
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
10,777
—
—
—
—
—
—
—
10,401
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
16,500
14,894
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
8,221
—
40,982
—
—
—
—
—
—
—
—
—
—
—
—
7,025
—
—
—
—
—
—
—
—
—
8,914
—
—
14,393
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
15,346
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
23,446
54,241
41,016
—
—
13,964
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
93,716
—
—
—
—
—
5,881
8,512
29,590
30,321
2,046
9,402
729
35,100
39,518
10,296
4,061
1,678
13,421
3,168
3,109
40,236
83,836
106,898
481
230
89,194
996
5,345
16,325
10,149
1,112
1,656
639
996
789
516
1,142
2,132
7,023
2,599
3,517
8,221
1,858
266,711
63,664
710
64,728
627
1,260
32
Table 8—Estimated carbon mass of all live trees on forest land by species and diameter class (continued)
Diameter class (inches)
Species
5.0–6.9
7.0–8.9
9.0–
10.9
Pouteria obovata
Pouteria sp.
Premna obtusifolia
Pterocarpus indicus
Ptychosperma palauensis
Rhizophora apiculata
Rhizophora mucronata
Rhus taitensis
Rinorea carolinensis
Semecarpus venenosus
Sonneratia alba
Stemonurus ammui
Swietenia macrophylla
Swietenia mahagoni
Symplocos racemosa
Terminalia catappa
Theobroma cacao
Timonius subauritus
Tournefortia argentea
Trichospermum ledermannii
Vitex cofassus
Xylocarpus granatum
Unknown 0
Unknown 1
Unknown 3
Unknown 5
Unknown 11
Unknown, other
4,236
—
999
—
2,463
24,186
6,386
2,259
—
9,042
184
—
1,156
1,717
1,006
—
237
1,319
173
1,014
—
1,395
943
275
—
349
530
399
8,257
678
932
—
—
19,925
5,937
5,683
350
6,672
1,331
553
—
681
752
1,529
1,471
1,466
351
2,255
713
891
—
378
—
—
1,843
—
6,767
—
—
—
—
10,339
1,434
4,594
—
7,472
—
—
998
1,563
—
3,146
—
1,030
915
3,035
—
2,882
—
—
988
—
1,646
1,098
5,580
—
—
—
—
4,792
3,976
9,211
—
6,979
1,169
—
—
—
—
2,761
3,129
—
—
2,053
—
1,398
—
—
—
1,441
—
—
—
—
—
—
—
6,909
—
11,437
—
2,443
—
—
—
—
—
—
—
—
1,124
—
2,499
4,342
—
—
—
—
—
—
—
—
—
1,869
—
—
—
3,881
—
4,120
4,216
4,955
—
—
—
—
—
3,432
—
—
5,590
—
—
—
—
—
—
—
309,072
238,270
218,124
249,022
170,274
164,318
Total
11.0–
12.9
13.0–
14.9
15.0–
16.9
17.0–
18.9
19.0–
20.9
Tons
4,659
3,074
—
—
—
—
—
—
—
—
—
—
—
—
4,390
—
—
—
—
—
—
—
6,328
13,336
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
3,411
—
1,875
—
—
—
—
—
—
—
—
—
—
—
—
—
122,568
92,506
21.0–
22.9
23.0–
24.9
25.0–
26.9
27.0–
28.9
29.0+
All
classes
—
—
—
3,975
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
9,828
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
8,022
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
10,701
—
—
—
—
—
—
—
—
—
—
7,238
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
17,775
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
10,684
65,373
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
11,274
32,573
678
1,932
5,843
2,463
66,151
17,732
41,455
350
58,113
90,049
25,172
2,153
3,961
1,758
7,435
4,836
7,247
2,564
8,358
37,300
12,784
943
653
988
1,790
4,019
12,771
94,899
106,412
123,441
63,454
344,168
2,296,529
Palau’s Forest Resources, 2003
Number of Canopy and Understory Species
In addition to counting and measuring overstory trees, understory vegetation
cover and layer heights were estimated for shrubs, forbs, vines, and grasses on
FIA subplots where a species occupied at least 3 percent cover on that subplot
(table 9). Tree seedlings that are less than or equal to 1 inch in diameter are
also estimated as understory vegetation cover (table 10). Special interest species
(e.g., rare, endangered, medicinal, or invasive) identified by island foresters were
also noted when found. However, if a species covered less than 3 percent of a
subplot and it was not listed as special interest, it was not enumerated.
Table 9—Average nontree understory cover a on FIA field subplots by species and forest type
Forest type
Volcanic
Scientific name
Cover
Achyranthes aspera L.
Adiantum philippense L.
Alpinia carolinensis Koidz.
Alpinia pubiflora K.Schum.
Alpinia purpurata (Vieill.) K. Schum.
Alpinia sp. Roxb.
Angiopteris evecta (J.R. Forst.) Hoffman
Antrophyum plantagineum (Cav.) Kaulf.
Asplenium nidus L.
Asplenium pellucidum Lam.
Asplenium polyodon G. Forst.
Bambusa vulgaris Schrad. ex J.C. Wendl.
Blechnum orientale L.
Bolbitis sp. Schott.
Caesalpinia major (Medik.) Dandy & Exell
Caesalpinia sp. L.
Calamus sp. L.
Cassytha filiformis L.
Centotheca lappacea (L.) Desv.
Cheilanthes tenuifolia (Burmann) Swartz
Clerodendrum sp. L.
Clidemia hirta (L.) D. Don
Clidemia sp. D. Don
Combined ferns
Costus speciosus Smith
Cyperus sp. L.
Cyrtosperma chamissonis (Schott) Merrill
Dalbergia palauensis Hosokawa
Davallia solida (Forster fil.) Swartz. Schrad
Davallia sp. Sm.
Decaspermum raymundii Diels
Decaspermum sp. J. R. Forst. & G. Forst.
Derris sp. Lour.
Derris trifoliata Lour.
Percent
2.0
4.8
9.6
5.0
3.3
3.2
3.7
—
1.6
—
1.0
2.0
4.6
3.3
1.0
2.0
1.0
6.0
1.3
1.0
1.0
1.3
1.0
1.0
2.2
50.0
8.3
3.0
1.7
3.0
2.0
2.0
35.0
19.0
Number of
subplots
1
4
14
3
3
13
3
—
65
—
1
1
16
3
1
1
1
3
3
1
2
4
1
2
5
1
3
1
3
5
1
2
4
5
Limestone
Standard
deviation
Cover
—
4.1
17.6
4.4
3.2
3.0
2.5
—
1.02
—
—
—
6.1
4.0
—
—
—
7.8
0.6
—
0.0
0.5
—
0.0
1.1
—
10.1
—
1.2
1.9
—
1.4
12.9
13.4
Percent
—
—
—
—
—
—
—
1.0
1.4
2.0
2.1
—
—
—
—
—
5.0
—
—
—
—
—
—
—
—
—
—
—
1.5
—
—
—
—
—
Number of
subplots
—
—
—
—
—
—
—
2
23
1
10
—
—
—
—
—
2
—
—
—
—
—
—
—
—
—
—
—
4
—
—
—
—
—
Standard
deviation
—
—
—
—
—
—
—
0.0
0.7
—
2.1
—
—
—
—
—
4.2
—
—
—
—
—
—
—
—
—
—
—
0.6
—
—
—
—
—
33
RESOURCE BULLETIN PNW-RB-252
Table 9—Average nontree understory cover a on FIA field subplots by species and forest type (continued)
Forest type
Volcanic
Scientific name
Cover
Dianella sp. Lam.
Dioscorea alata L.
Dioscorea bulbifera L.
Dioscorea sp. L.
Donax cannaeformis (Forst. f.) K. Schum.
Donax sp. Lour.
Eriachne pallescens R. Br.
Eurya japonica (Korth.) This.-Dyer
Eustachys petraea (Sw.) Desv.
Ficus sp. L.
Ficus tinctoria Forst. f.
Flagellaria gigantea Hook f.
Freycinetia villalobosii Martelli
Gleichenia linearis (Luers.) Fosberg
Gliricidia sp. (Blank)
Hanguana malayana Merrill
Hedyotis cornifolia Kaneh.
Hedyotis korrorensis (Valeton) Hosok.
Hedyotis sp. L.
Heterogonium pinnatum (Copel.) Holtt.
Hippobroma longiflora (L.) G. Don
Hyptis capitata Jacq.
Ipomea sp. L.
Ischaemum polystachyum J. S. Presl
Ixora casei Hance
Ixora sp. L.
Lantana camara L.
Lindsaea obtusa J. Sm. Hook.
Lycopodium cernuum L.
Lycopodium phlegmaria L.
Lygodium auriculatum (Willd.) Alston
Lygodium circinnatum (Burm. f.) Sw.
Machaerina mariscoides (Gaud.) J. Kern
Macrothelypteris torresiana (Gaud.)
Medinilla blumeana Mansfeld
Melastoma malabathricum L.
Merremia peltata (L.) Merrill
Merremia sp. Dennst. Ex Endl.
Microsorum scolopendria (Burm. f.)
Mimosa pudica L.
Mussaenda frondosa L.
Nepenthes mirabilis Druce
Nephrolepis acutifolia (Desv.) J. Christ
Nephrolepis biserrata (Sw.) Schott
Nephrolepis hirsutula (J.R. Forst.) K. Presl
Pandanus aimiriikensis Martelli
Pandanus sp. L. f.
Paspalum conjugatum Berg.
Pennisetum polystachyon (L.) J.A. Schultes
Phaleria nisidai Kaheh.
Phragmites karka (Retz.) Trin. ex Steud.
Percent
1.7
5.0
1.5
3.0
11.0
24.0
45.0
7.8
4.7
1.5
6.5
1.0
23.8
47.1
15.0
19.0
2.0
1.0
3.6
2.0
1.0
1.5
—
17.7
4.7
2.8
2.5
1.1
10.9
1.0
1.7
6.6
5.3
2.5
1.0
1.5
25.3
1.5
2.2
2.0
2.0
1.2
2.0
2.0
9.9
10.7
4.6
11.4
1.0
2.0
25.3
34
Number of
subplots
3
4
2
1
9
3
4
10
3
4
2
1
6
20
1
4
7
1
5
1
1
2
—
3
3
37
2
14
11
1
9
5
19
2
2
16
19
2
5
1
1
25
1
4
7
9
68
5
1
1
3
Limestone
Standard
deviation
Cover
1.2
1.6
0.7
—
11.9
23.3
5.8
9.9
0.6
1.0
2.1
—
29.3
38.3
—
14.5
1.2
—
3.7
—
—
0.7
—
19.7
2.9
3.1
0.7
0.3
9.0
—
0.9
3.2
7.3
0.7
0.0
0.9
28.8
0.7
1.6
—
—
0.4
—
0.8
15.8
24.2
5.9
8.3
—
—
22.4
Percent
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
1.0
—
—
5.0
—
2.0
—
—
—
—
—
—
—
—
5.0
—
2.7
—
—
—
—
24.7
—
—
2.0
—
—
—
—
Number of
subplots
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
1
—
—
1
—
1
—
—
—
—
—
—
—
—
1
—
19
—
—
—
—
13
—
—
1
—
—
—
—
Standard
deviation
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
3.3
—
—
—
—
30.2
—
—
—
—
—
—
—
Palau’s Forest Resources, 2003
Table 9—Average nontree understory cover a on FIA field subplots by species and forest type (continued)
Forest type
Volcanic
Scientific name
Phyllanthus sp. L.
Piper fragile Benth.
Piper sp. L.
Pityrogramma calomelanos (L.) Link
Polypodium punctatum (Raddi) Hook.
Polyscias grandifolia Volk.
Portulaca oleracea L.
Pteris ensiformis Burm. f.
Pteris plumula Desv auct. Non Retz.
Pteris tripartita Sw.
Pteris vittata L.
Rhaphidophora carolinensis (Volk.) Fosberg
Rhaphidophora sp. Hassk.
Rhaphidophora versteegii Engl. & K. Krause
Rhynchospora sp. Vahl
Scaevola sericea Vahl var. taccada (Gaertn.) Thieret
& B. Lipscomb
Schefflera odorata Merr. & Rolfe
Schefflera sp. J.R. & G. Forst.
Schizaea dichotoma (L.) Sm.
Scleria levis Willd.
Spathoglottis carolinensis Schlecht.
Thelypteris forsteri Morton
Thelypteris parasitica (L.) Reed.
Thelypteris sp. Schmidel
Thelypteris unita (L.) C.V. Morton
Vernonia sp. Schreb.
Vitex sp. L.
Vitex trifolia L.
Wikstroemia elliptica Merr.
Unknown annual grass 1
Unknown fern 0
Unknown fern 1
Unknown fern 2
Unknown fern 3
Unknown fern 4
Unknown forb 1
Unknown forb 2
Unknown grass 1
Unknown orchid 0
Unknown perennial grass 1
Unknown perennial grass 1a
Unknown perennial grass 2
Unknown shrub 0
Unknown shrub 2
Unknown vine 1
Unknown vine 2
Unknown vine 3
a Cover
Number of
subplots
Limestone
Standard
deviation
Cover
0.6
—
—
0.0
0.0
19.4
13.2
—
—
0.7
0.0
1.4
1.0
2.7
—
Percent
—
—
5.5
—
—
—
—
—
—
—
—
—
—
2.5
—
Percent
1.3
1.0
1.0
1.0
1.0
22.5
25.0
2.0
2.0
1.6
1.0
2.0
1.5
2.5
25.0
3
1
1
2
2
4
3
1
1
8
2
2
4
23
1
5.0
1
—
17.3
1.0
1.2
3.0
1.7
6.0
2.0
3.0
6.2
2.0
—
25.0
2.4
4.3
1.0
12.8
8.0
1.0
1.0
3.6
3.3
1.0
2.8
13.6
1.0
45.5
3.1
5.0
2.8
3.0
25.0
3
2
20
8
3
1
3
1
24
3
—
1
5
4
1
6
4
1
2
11
3
1
5
13
1
2
7
1
9
1
1
14.2
0.0
0.5
2.1
0.6
—
1.0
—
14.2
1.0
—
—
1.7
4.3
—
28.0
9.1
—
0.0
2.7
1.5
—
4.0
18.8
—
62.9
5.2
—
4.6
—
—
Number of
subplots
Standard
deviation
—
—
6
—
—
—
—
—
—
—
—
—
—
11
—
—
—
5.9
—
—
—
—
—
2.0
—
—
—
—
—
—
1.0
—
5.6
—
—
—
—
1.5
2.0
—
—
3.0
2.0
—
1.0
—
—
—
1.6
—
2.0
1.0
—
—
2
—
—
—
—
—
—
1
—
7
—
—
—
—
4
2
—
—
1
2
—
1
—
—
—
11
—
5
1
—
—
0.0
—
—
—
—
—
—
—
—
10.8
—
—
—
—
0.6
0.0
—
—
—
1.4
—
—
—
—
—
0.7
—
0.7
—
—
—
—
—
—
—
—
—
—
1.3
—
Percentage cover of “1” indicates cover less than or equal to 1 percent. Cover estimates are averaged among subplots where each
species was found. A total of 188 subplots was surveyed for vegetation cover. The number of subplots where a species was found and the
standard deviation for cover estimates provide an idea of spatial variability for each species across the island group.
35
RESOURCE BULLETIN PNW-RB-252
Table 10—Average understory tree cover a on FIA field subplots by species and forest type
Forest type
Volcanic
Scientific name
Cover
Aglaia palauensis Kaneh.
Aidia cochinchinensis Lour.
Allophylus ternatus (Forst.) Radlk.
Alphitonia carolinensis Hosok.
Alphitonia zizyphoides A. Gray
Areca catechu L.
Astronidium palauense (Kaneh.) Mgf.
Astronidium sp. A. Gray
Badusa palauensis Valeton
Barringtonia asiatica (L.) Kurz
Barringtonia racemosa (L.) Spreng.
Bruguiera gymnorrhiza (L.) Lam.
Buchanania engleriana Volk.
Buchanania palawensis Lauterb.
Buchanania sp. Spreng.
Calophyllum inophyllum L.
Calophyllum pelewense P. F. Stevens
Campnosperma brevipetiolata Volk.
Canarium hirsutum Willd.
Casuarina equisetifolia L.
Cerbera manghas L.
Cerbera sp. L.
Cocos nucifera L.
Commersonia bartramia (L.) Merr.
Cyathea lunulata (Forst. f.) Copel.
Diospyros discolor Willd.
Diospyros ferrea (Willd.) Bakh.
Diospyros sp. L.
Dracaena multiflora Tentative
Drypetes nitida Kaneh.
Dysoxylum sp. Blume
Elaeocarpus joga Merr.
Elaeocarpus sp. L.
Elattostachys falcata (Seem.) Radik.
Eugenia cumini (L.) Druce
Eugenia javanica Lam.
Eugenia reinwardtiana (Bl.) DC.
Eugenia sp. L.
Evodia sp. Lam.
Fagraea ksid Gilg and Bened.
Ficus sp. L.
Ficus tinctoria Forst. f.
Flacourtia rukam Zoll. & Moritzi
Garcinia matudai Kaneh.
Garcinia rumiyo Fosb.
Percent
2.4
—
2.0
3.3
2.0
3.0
1.4
1.0
2.0
—
5.9
1.6
1.0
3.0
5.5
1.5
2.3
2.8
7.0
—
2.8
1.0
3.8
1.0
4.3
2.5
2.5
2.5
—
—
2.4
2.2
1.0
1.0
2.0
—
6.6
1.9
2.0
1.0
2.3
5.3
2.8
6.8
8.2
36
Number of
subplots
21
—
1
6
1
3
11
1
1
—
7
15
1
1
2
2
4
9
2
—
4
1
9
1
4
2
2
2
—
—
7
5
1
1
1
—
7
8
1
1
3
19
5
4
19
Limestone
Standard
deviation
Cover
1.6
—
—
2.7
—
2.0
0.7
—
—
—
6.5
1.4
—
—
3.5
0.7
1.5
2.9
1.4
—
1.7
—
4.3
—
3.9
0.7
0.7
0.7
—
—
1.0
1.3
—
—
—
—
8.4
1.0
—
—
0.6
4.4
1.5
9.0
12.5
Percent
2.3
1.5
—
—
—
—
—
—
2.8
1.0
3.0
—
—
—
—
2.2
—
—
—
2.0
—
—
34.0
—
—
—
—
—
3.0
3.0
—
8.0
—
—
4.8
1.8
4.3
3.3
—
—
—
2.4
—
—
—
Number of
subplots
4
2
—
—
—
—
—
—
4
1
1
—
—
—
—
5
—
—
—
1
—
—
3
—
—
—
—
—
1
1
—
1
—
—
4
8
9
3
—
—
—
7
—
—
—
Standard
deviation
0.5
0.7
—
—
—
—
—
—
0.5
—
—
—
—
—
—
0.8
—
—
—
—
—
—
29.5
—
—
—
—
—
—
—
—
—
—
—
2.8
0.7
2.8
1.5
—
—
—
1.3
—
—
—
Palau’s Forest Resources, 2003
Table 10—Average understory tree cover a on FIA field subplots by species and forest type (continued)
Forest type
Volcanic
Scientific name
Garcinia sp. L.
Glochidion ramiflorum Forst.
Glochidion sp. J.R. & G. Forst.
Gmelina elliptica Sm.
Gmelina palawensis H. J. Lam.
Gulubia palauensis (Becc.) Moore & Fosb.
Heterospathe elata (Becc.) Becc.
Hibiscus tiliaceus L.
Horsfieldia amklaal Kaneh.
Horsfieldia novo-guineensis Warb.
Horsfieldia palauensis Kaneh.
Horsfieldia sp. Wild.
Inocarpus fagifer (Park.) Fosb.
Macaranga carolinensis Volk.
Manilkara udoido Kaneh.
Manilkara zapota (L.) P. v. Roy.
Melochia aristata A. Gray
Morinda citrifolia L.
Morinda pedunculata Val.
Myristica sp. Gronov.
Neonauclea forsteri Merrill
Omalanthus sp. A.Juss.
Ormosia calavensis Azaola ex Blanco
Osmoxylon oliveri Fosberg & Sachet
Osmoxylon pachyphyllum (Kanehira) F.R. Fosberg
& M.-H. Sachet
Osmoxylon sp. Miq.
Pandanus aimiriikensis Mart.
Pandanus dubius Spr.
Pandanus kanehirae Mart.
Pandanus peliliuensis Kaneh.
Pandanus tectorius Park.
Parinari corymbosum (Bl.) Miq.
Parinari laurina Gray
Parkia parvifoliola Hosok.
Pinanga insignis Becc.
Pithecellobium dulce (Roxb.) Benth.
Polyscias nodosa (Bl.) Seem.
Pongamia pinnata (L.) Merr.
Pouteria calcarea (Hosok.) Fosb.
Pouteria obovata (R. Br.) Baehni
Premna obtusifolia R. Br.
Rhizophora apiculata Bl.
Rhizophora mucronata Lam.
Rhus taitensis Guill.
Cover
Number of
subplots
Limestone
Standard
deviation
Cover
Percent
7.8
2.0
1.0
2.0
—
2.0
2.0
—
2.5
—
2.2
—
—
5.5
—
—
—
—
—
—
—
—
—
—
Percent
4.3
3.0
—
—
1.5
9.3
4.2
5.0
3.0
4.5
4.3
2.5
2.0
3.1
2.0
1.7
2.0
1.5
21.5
2.0
4.0
11.5
2.0
5.0
4
4
—
—
2
3
6
8
2
15
45
2
2
17
5
3
1
4
2
1
1
4
1
4
3.9
1.4
—
—
0.7
5.1
2.0
5.1
—
3.1
10.6
0.7
1.4
3.0
1.4
0.6
—
0.6
26.2
—
—
12.3
—
5.0
3.0
1
—
3.0
3.5
—
1.5
—
3.1
8.0
30.8
1.0
19.9
—
—
—
—
1.5
5.0
13.9
1.5
1.9
10
10
—
2
—
8
4
12
1
103
—
—
—
—
2
1
15
2
8
3.3
2.8
—
0.7
—
2.4
11.4
27.5
—
20.6
—
—
—
—
0.7
—
23.9
0.7
1.4
Number of
subplots
Standard
deviation
5
2
1
1
—
1
1
—
2
—
10
—
—
2
—
—
—
—
—
—
—
—
—
—
6.9
—
—
—
—
—
—
—
0.7
—
0.8
—
—
3.5
—
—
—
—
—
—
—
—
—
—
—
—
—
1.0
27.0
2.5
—
1.5
—
—
2.0
—
1.5
1.8
3.0
2.0
1.0
1.6
—
1.0
—
2.0
1
3
6
—
2
—
—
1
—
4
4
1
1
1
7
—
4
—
1
—
37.5
1.6
—
0.7
—
—
—
—
0.6
0.5
—
—
—
0.5
—
—
—
—
37
RESOURCE BULLETIN PNW-RB-252
Table 10—Average understory tree cover a on FIA field subplots by species and forest type (continued)
Forest type
Volcanic
Scientific name
Cover
Semecarpus venenosus Volk.
Sonneratia alba J. E. Sm.
Stemonurus ammui (Kaneh.) Sleumer
Swietenia mahagoni (L.) Jacq.
Symplocos racemosa Roxb.
Tecoma stans (L.) Juss. ex HBK.
Terminalia catappa L.
Terminalia sp. L.
Timonius subauritus Fosberg & Sachet
Trichospermum ledermannii Burret
Xylocarpus granatum Koen.
Unknown 0
Unknown 1
Unknown 20
Percent
2.2
2.8
40.0
6.0
2.3
3.0
3.0
20.0
—
1.0
1.6
1.3
2.0
2.0
Number of
subplots
31
8
1
2
6
1
1
1
—
2
8
4
1
1
Limestone
Standard
deviation
Cover
1.6
3.1
—
2.8
0.8
—
—
—
—
—
1.4
0.5
—
—
Percent
3.0
—
—
—
—
—
—
—
8.5
—
—
—
—
—
Number of
subplots
1
—
—
—
—
—
—
—
2
—
—
—
—
—
Standard
deviation
—
—
—
—
—
—
—
—
9.2
—
—
—
—
—
a Percentage cover of “1” indicates cover less than or equal to 1 percent. Cover estimates are averaged among subplots where each
species was found. A total of 188 subplots was surveyed for vegetation cover. The number of subplots where a species was found and
the standard deviation for cover estimates provide an idea of spatial variability for each species across the island group.
For the 2003 inventory, 128 tree species and 132 understory species were
measured on FIA plots. The volcanic forest area sampled was about four times the
area sampled for the limestone forest. Because we expect the number of species
counted to increase with increasing area, it is not surprising that over twice the
number of tree species and over four times the number of understory species were
found in volcanic forest compared to limestone forest (fig. 11). On a per-plot basis
(approximately one-sixth acre), the mean number of tree species found on volcanic
plots was 12, with an average of 10 tree species found per limestone plot (fig. 12).
The one limestone plot where only two species occurred (fig. 12) was a mangrove
plot where 90 trees (>5 inches) were measured, 65 Rhizophora apiculata and 25
R. mucronata. The area of mangrove forest could not be accurately delineated from
limestone forest with this small sample, thus separate expansion factors were not
calculated for mangrove species. Mangrove species numbers may be falsely high
owing to this expansion. However, because mangrove species tend to dominate the
extensive mangroves on Palau, and only five partial plots contained mangrove
species, the estimate may be reasonable. Additional mapping data are forthcoming
and will help refine our estimate for mangrove species. The urgent need to better
understand mangroves as buffers to coastal disturbance (storms, typhoons, and
tsunami) suggests the need for a separate, detailed mangrove inventory.
38
Palau’s Forest Resources, 2003
140
Number of species
120
Volcanic
100
Limestone
80
60
40
20
0
Tree species
Understory species
Number of plots
Figure 11—One hundred and twenty-eight tree species and 132 understory species were measured on
54 forested plots in Palau.
10
Number of plots
9
8
Volcanic
7
Limestone
6
5
4
3
2
1
0
1–2
3–4
5–6
7–8
9–10 11–12 13–14 15–16 17–18 19–20
Number of tree species on FIA plots
Figure 12—The average number of tree species found per sixth-acre plot was 12 for volcanic forests
and 10 for limestone forests.
39
RESOURCE BULLETIN PNW-RB-252
Tree Damage and Mortality
Approximately 13 percent of the individual trees on Palau show some sign of damage (table 11). The most prevalent damage types are vines in crowns, conks (shelf
fungus indicating rot), and lost apical dominance (damage to the primary growing leader) (fig. 13). The prevalence of vines in tree crowns was high, 41 percent.
Although the vines are common, their effect on their supporting tree hosts was not
quantified. Effects ranged from some additional weight to rare instances of strangulation. For the identifiable damaging agents, damage by other vegetation, disease,
and weather ranked as the most prevalent primary damage agents (fig. 14).
Less than 5 percent of the trees sampled during the inventory were dead (fig.
15). Of those dead, nearly one-fourth could not be identified to species level. The
most prevalent, identifiable dead trees were Cyathea lunulata (7.3 percent of total
dead), Calophyllum inophyllum, Calophyllum pelewense, and Pinanga insignis
(each accounting for 6.1 percent of total dead).
Epiphytes—
In the moist environment of the tropics many plant species are found growing on
longer lived trees. These epiphytes use the trees primarily for support, but they
also use space, moisture, and nutrients that might otherwise be used by the tree.
When the epiphytes accumulate over many years, their weight can be excessive,
leading to the breakage of branches and occasionally the stems of trees. In Palau we
rated epiphytic loading on trees as a summation of loading on the bole, branches,
and canopy. We estimate that about 65 percent of the trees in Palau had few to no
epiphytes, and 45 percent of the trees had moderate to high amounts of epiphytes
(table 12).
Forest Dynamics—
Forest structure and species composition change through time as a result of forest
succession and disturbance dynamics. The forests of Palau have been strongly
influenced by a long history of disturbance, both human-caused and climatic
disturbance. Human populations and land use on Palau have changed, resulting in
differing influences on forest vegetation. Within the last century, the most important land use changes have involved the conversion of forest to agriculture and its
subsequent abandonment and reversion to grassland, and eventually forest. Endress
and Chinea (2001) documented the abandonment of agricultural lands and reversion
to forest by comparing 1947 and 1992 aerial photography for approximately 20,500
acres in the Ngeremeduu Bay drainage area on Babeldaob. These authors noted the
most dramatic change occurred during the period 1947 to 1976, using the Cole et al.
(1987) map as an intermediate comparison point. (Text continues on page 49.)
40
Table 11—Number of trees by primary damage type and species for all trees (≥5 inches diameter at breast height; includes dead trees)
Species
Broken Broken Broken Canker/
bole branches roots
gall
Conks
Cracks/ Discolored Excessive Lost apical Open
seams
foliage
branching dominance wound
Number of trees
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
171,813
36,989
12,330
456,192
12,330
73,977
48,518
258,920
12,330
254,719
330,896
468,521
98,436
293,308
197,072
49,318
36,588
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
24,659
—
—
—
—
—
—
—
—
—
12,129
—
—
—
12,129
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
12,330
—
—
—
—
—
—
—
—
12,330
—
—
—
12,330
12,330
12,129
12,129
—
—
—
12,330
—
—
714,911
—
24,659
12,330
—
24,659
—
72,777
12,330
84,906
60,647
24,659
135,425
306,637
12,330
12,330
542,498
98,636
73,577
73,177
98,036
36,788
36,989
—
453,391
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
12,129
—
—
—
—
—
12,330
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
12,129
—
—
—
24,659
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
Vines in
crown
All
damages
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
12,330
—
—
—
—
—
—
12,330
—
12,129
—
—
—
—
—
—
—
—
—
—
12,330
—
—
—
—
—
—
—
—
—
24,259
—
—
—
49,318
—
—
12,330
—
—
—
—
—
12,129
36,989
—
—
—
—
—
12,129
61,648
—
—
36,989
—
—
—
24,659
12,330
48,518
49,118
12,330
—
36,388
12,330
—
36,788
—
—
—
—
61,648
123,295
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
12,330
—
—
—
—
—
12,330
12,330
—
—
—
—
12,330
—
—
—
—
—
—
—
—
—
—
—
12,330
12,330
—
—
—
—
61,648
12,330
—
—
—
—
—
—
—
—
—
12,330
24,459
24,659
—
—
12,129
—
73,977
12,330
—
—
12,330
—
12,330
—
12,129
—
—
12,330
73,777
Palau’s Forest Resources, 2003
41
Aglaia palauensis
Allophylus ternatus
Allophylus timorensis
Alphitonia carolinensis
Annona reticulata
Areca catechu
Artocarpus mariannensis
Astronidium palauense
Avicennia marina
Badusa palauensis
Barringtonia racemosa
Bruguiera gymnorrhiza
Buchanania palawensis
Calophyllum inophyllum
Calophyllum pelewense
Calophyllum soulattri
Calophyllum sp.
Campnosperma
brevipetiolata
Canarium hirsutum
Casearia cauliflora
Casearia sp.
Casuarina equisetifolia
Cerbera floribunda
Cerbera manghas
Cocos nucifera
Commersonia bartramia
Cordia micronesica
Cyathea lunulata
Diospyros ferrea
Diospyros sp.
Dodonaea viscosa
Dracaena multiflora
Drypetes nitida
Dysoxylum sp.
Elaeocarpus graeffei
Elaeocarpus joga
No
damage
(continued)
Species
No
damage
Erythrina fusca
Eugenia cumini
Eugenia javanica
Eugenia reinwardtiana
Eugenia sp.
Fagraea ksid
Ficus sp.
Ficus tinctoria
Flacourtia rukam
Garcinia matudai
Garcinia rumiyo
Garcinia sp.
Gironniera celtidifolia
Glochidion ramiflorum
Glochidion sp.
Gmelina elliptica
Gmelina palawensis
Gmelina sp.
Gulubia palauensis
Hernandia sonora
Hernandia sp.
Heterospathe elata
Hibiscus tiliaceus
Horsfieldia amklaal
Horsfieldia novo-guineensis
Horsfieldia palauensis
Horsfieldia sp.
Inocarpus fagifer
Intsia bijuga
Lumnitzera littorea
Macaranga carolinensis
Manilkara udoido
Manilkara zapota
Morinda citrifolia
Morinda latibracteata
12,129
207,201
181,942
570,685
36,788
110,966
12,330
24,259
135,425
49,318
294,908
343,626
36,989
134,224
—
182,342
431,133
36,989
109,165
12,129
36,388
73,977
49,318
220,531
221,931
845,935
—
12,330
181,942
12,330
122,695
234,261
49,318
—
24,659
Broken Broken Broken Canker/
bole branches roots
gall
Conks
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
12,330
—
—
—
—
—
—
—
12,129
—
12,129
—
—
—
—
—
—
—
—
—
24,459
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
12,330
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
24,259
—
—
12,330
—
—
—
—
12,330
—
—
12,330
—
24,659
61,648
—
—
12,129
12,129
—
—
12,330
12,330
36,588
12,330
—
36,388
—
12,330
—
—
12,330
12,330
Cracks/ Discolored Excessive Lost apical Open
seams
foliage
branching dominance wound
Number of trees
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
12,129
12,330
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
24,659
—
—
—
—
12,330
—
36,989
—
—
—
—
—
12,330
12,330
—
24,659
—
—
—
—
—
—
12,330
—
—
—
—
24,259
24,259
—
—
—
—
—
—
—
—
—
—
—
—
36,788
12,330
—
—
12,129
—
—
—
—
12,330
—
—
12,129
—
—
—
—
—
—
Vines in
crown
All
damages
—
12,129
—
—
—
36,989
—
—
—
—
12,330
—
—
36,788
12,330
—
—
24,659
—
12,129
—
12,330
36,989
—
—
49,118
—
—
—
—
36,989
36,989
12,330
12,330
24,659
—
12,129
48,518
24,259
—
61,648
—
—
24,459
24,659
24,659
—
—
61,247
24,659
36,788
135,425
36,989
—
24,259
24,259
12,330
49,318
24,659
12,330
147,154
12,330
—
48,518
—
49,318
49,318
24,659
24,659
36,989
RESOURCE BULLETIN PNW-RB-252
42
Table 11—Number of trees by primary damage type and species for all trees (≥5 inches diameter at breast height; includes dead trees)
Table 11—Number of trees by primary damage type and species for all trees (≥5 inches diameter at breast height; includes dead trees)
(continued)
Species
No
damage
Broken Broken Broken Canker/
bole branches roots
gall
Conks
Cracks/ Discolored Excessive Lost apical Open
seams
foliage
branching dominance wound
Vines in
crown
All
damages
Number of trees
Morinda sp.
—
—
—
—
—
—
—
—
12,330
—
24,659
24,659
61,648
145,554
61,648
86,307
12,330
12,330
554,428
516,039
24,659
2,071,357
12,129
36,989
353,555
12,330
36,989
24,659
86,307
1,343,843
377,214
357,556
12,129
528,168
172,613
61,648
49,318
36,989
36,989
12,330
24,659
84,906
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
12,330
—
—
—
—
—
—
—
—
—
—
12,129
—
12,330
—
—
—
—
—
—
12,330
—
—
—
—
—
—
—
—
48,518
—
12,330
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
12,330
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
49,318
24,659
—
—
—
—
24,659
—
—
—
—
12,129
—
12,330
—
12,330
—
—
—
—
—
—
24,659
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
12,330
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
12,330
—
—
—
—
—
12,129
—
—
—
—
12,330
—
—
—
—
—
—
—
—
—
—
12,129
—
12,330
—
12,330
—
—
—
—
12,330
—
12,330
—
12,330
—
—
—
—
—
—
—
—
—
—
12,330
—
—
—
—
—
—
—
—
—
—
12,330
—
12,330
—
—
—
—
—
—
—
—
—
—
—
—
12,330
—
36,989
—
—
—
—
—
12,330
12,330
24,659
—
123,295
—
—
24,459
—
49,318
—
—
—
—
12,330
—
24,659
—
—
—
36,989
—
36,989
—
24,259
24,659
—
12,330
—
36,989
—
60,647
—
12,330
—
12,330
110,966
49,318
—
123,295
—
—
49,118
—
49,318
—
—
48,718
—
73,977
—
49,318
—
—
—
36,989
24,659
36,989
36,989
24,259
Palau’s Forest Resources, 2003
43
Morinda pedunculata
Nephelium lappaceum
Osmoxylon oliveri
Osmoxylon sp.
Pandanus aimiriikensis
Pandanus dubius
Pandanus kanehirae
Pandanus tectorius
Pandanus utiyamai
Pangium edule
Parinari corymbosum
Parinari laurina
Parinari sp.
Pinanga insignis
Pithecellobium dulce
Pouteria calcarea
Pouteria obovata
Pouteria sp.
Premna obtusifolia
Pterocarpus indicus
Ptychosperma palauensis
Rhizophora apiculata
Rhizophora mucronata
Rhus taitensis
Rinorea carolinensis
Semecarpus venenosus
Sonneratia alba
Stemonurus ammui
Swietenia macrophylla
Swietenia mahagoni
Symplocos racemosa
Terminalia catappa
Theobroma cacao
Timonius subauritus
12,330
(continued)
Species
Tournefortia argentea
Trichospermum ledermanni
Vitex cofassus
Xylocarpus granatum
Unknown
Unknown 0
Unknown 1
Unknown 3
Unknown 5
Unknown 10
Unknown 11
Unknown 30
Unknown, other
Total
No
damage
36,588
98,636
61,648
147,954
12,330
134,824
24,659
49,318
85,906
12,330
12,330
12,129
73,977
18,714,675
Broken Broken Broken Canker/
bole branches roots
gall
Conks
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
12,330
—
—
—
—
—
—
—
24,659 195,872
—
—
—
—
—
—
—
—
—
—
—
—
—
97,836
—
—
—
—
—
—
—
—
—
—
—
—
—
12,330
—
—
24,659
—
—
24,459
—
—
—
—
—
12,330
12,330 687,652
Cracks/ Discolored Excessive Lost apical Open
seams
foliage
branching dominance wound
Number of trees
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
12,129
12,330
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
12,330
295,308
—
—
12,330
12,330
—
—
—
—
—
—
—
—
—
Vines in
crown
All
damages
—
—
36,989
—
—
—
—
—
—
—
—
—
—
12,330
—
49,318
36,989
—
12,330
24,459
—
—
—
—
—
12,330
281,778 1,144,644 2,776,866
RESOURCE BULLETIN PNW-RB-252
44
Table 11—Number of trees by primary damage type and species for all trees (≥5 inches diameter at breast height; includes dead trees)
Palau’s Forest Resources, 2003
<1%
4%
1%
<1%
<1%
<1%
Tree damages
7%
Vines in crown
Conks
10%
Lost apical dominance
41%
Open wound
Broken branches
Broken roots
Broken bole
11%
Canker/gall
Discolored foliage
Excessive branching
Cracks/seams
25%
Figure 13—Vines in the crowns of trees are very common in Palau. Damage from vines was recorded when
the vines occupied 20 percent or more of the crown. Rot, indicated by the fruiting shelf fungi (conks) was
also a common damage.
2%
3%
<1%
<1%
11%
Primary damage agent
Vegetation
Disease
Unknown
11%
Weather
53%
Physical
Insect
Fire
Human
19%
Figure 14—Disturbance by other vegetation and disease were the most common identifiable damaging
agents for trees.
45
RESOURCE BULLETIN PNW-RB-252
25
Dead trees (percent)
20
15
10
5
Ca Cy All u
lop ath nk n
ow
Ca hyll ea
l o p u m lu n n
u
hy
i
llu nop lata
hy
m
Pi p e l e l l u m
na
we
n
Ca
So ga in nse
su
n
s
a r n er i g n
i na
is
Al
ati
ph
aa
ito equ
l
b
n
is e
a
P ia c
ti f
B a a r i na a r o l o l i a
i
rri
n r i c n en
Ho gton or ym sis
ia
r
r a bos
As sfiel
tr o d i a c em a
nid
o
p
ium alau sa
pa ens
El
ae
l
i
o c uae s
ns
ar
is
R pu
Rh
izo hus s jog
Ca
mp Ti pho taite a
no mo ra a nsi
s p n iu
p ic s
er
m a s s u u la t
br bau a
Di evip ritus
os
e
py tiol
ata
Ma
r
o
s
c a G ar
c i n fer r
ra
e
n
i
Pa ga c a ru a
a r m iy
nd
oli
an
n o
Pr us k ens
em
an
i
eh s
B a na
du o b i r a e
sa tus
i
p
Eu
C al fo l i
ge alop auen a
n ia
hy sis
G u r e i n l lu m
Rh lub war sp.
izo ia p dti
a
ph
a
or lau na
a m en
u c s is
ro
na
ta
0
Species
Figure 15—Identifying dead trees proved to be difficult in Palau. Nearly one-fourth of those dead could not be identified.
Table 12— Estimated number of trees on forest land by epiphyte loading (amounts of
nontree vegetation in the canopy and branches) and species (includes dead trees)
Epiphyte loadings
46
Species
None
Aglaia palauensis
Allophylus ternatus
Allophylus timorensis
Alphitonia carolinensis
Annona reticulata
Areca catechu
Artocarpus mariannensis
Astronidium palauense
Avicennia marina
Badusa palauensis
Barringtonia racemosa
Bruguiera gymnorrhiza
Buchanania palawensis
Calophyllum inophyllum
36,388
—
—
135,625
—
—
24,259
12,330
—
97,036
97,436
184,943
—
60,647
Low
123,095
12,330
—
160,284
—
36,989
—
135,625
12,330
145,554
134,624
234,261
49,118
146,154
Moderate
Number of trees
61,648
12,330
12,330
110,966
12,330
12,330
24,259
73,977
12,330
36,388
110,966
36,989
24,659
73,577
High
12,330
12,330
—
86,307
—
24,659
—
61,648
—
24,259
36,989
24,659
24,659
49,318
All loadings
197,072
36,989
12,330
357,556
12,330
73,977
24,259
271,249
24,659
206,201
282,578
295,908
98,436
269,049
Palau’s Forest Resources, 2003
Table 12— Estimated number of trees on forest land by epiphyte loading (amounts of
nontree vegetation in the canopy and branches) and species (includes dead trees)
(continued)
Epiphyte loadings
Species
None
Calophyllum pelewense
Calophyllum soulattri
Calophyllum sp.
Campnosperma brevipetiolata
Canarium hirsutum
Casearia cauliflora
Casearia sp.
Casuarina equisetifolia
Cerbera floribunda
Cerbera manghas
Cocos nucifera
Commersonia bartramia
Cordia micronesica
Cyathea lunulata
Diospyros ferrea
Diospyros sp.
Dodonaea viscosa
Dracaena multiflora
Drypetes nitida
Dysoxylum sp.
Elaeocarpus graeffei
Elaeocarpus joga
Erythrina fusca
Eugenia cumini
Eugenia javanica
Eugenia reinwardtiana
Eugenia sp.
Fagraea ksid
Ficus sp.
Ficus tinctoria
Flacourtia rukam
Garcinia matudai
Garcinia rumiyo
Garcinia sp.
Gironniera celtidifolia
Glochidion ramiflorum
Glochidion sp.
Gmelina elliptica
Gmelina palawensis
Gmelina sp.
Gulubia palauensis
Hernandia sonora
Hernandia sp.
Heterospathe elata
24,659
36,989
—
61,447
36,588
—
—
12,129
—
12,330
12,330
—
—
49,318
—
36,588
12,129
73,377
24,659
36,989
—
85,706
12,129
36,388
24,259
218,330
—
24,659
—
—
—
12,330
36,989
48,718
—
24,659
12,330
72,777
184,943
—
109,165
—
—
—
Low
86,106
12,330
48,918
332,897
12,129
12,330
84,906
—
24,659
98,436
159,083
12,330
—
98,636
49,318
49,318
48,718
24,459
12,129
—
—
269,649
—
97,836
121,295
340,025
—
24,659
—
12,129
85,906
36,989
85,706
233,260
24,659
85,306
—
72,777
221,331
36,989
—
—
60,647
73,977
Moderate
Number of trees
36,989
—
24,459
271,249
36,388
—
—
60,647
—
61,648
110,565
—
—
234,261
49,318
—
—
12,330
—
—
12,330
122,695
—
72,977
84,906
36,588
24,459
123,295
12,330
12,129
49,318
12,330
122,895
36,989
12,330
73,377
—
61,247
110,966
12,330
—
36,388
—
12,330
High
61,648
—
—
172,613
12,330
—
—
—
—
36,989
36,989
—
12,330
172,613
—
—
12,330
—
—
—
—
49,118
—
12,129
—
—
12,330
—
—
—
24,659
12,330
73,977
24,659
—
12,129
12,330
12,330
49,318
24,659
—
—
—
—
All loadings
184,743
12,330
73,377
776,759
60,847
12,330
84,906
60,647
24,659
197,072
306,637
12,330
12,330
505,510
98,636
49,318
61,047
36,788
12,129
—
12,330
441,462
—
182,942
206,201
376,613
36,788
147,954
12,330
24,259
159,883
61,648
282,578
294,908
36,989
170,813
12,330
146,354
381,615
73,977
—
36,388
60,647
86,307
47
RESOURCE BULLETIN PNW-RB-252
Table 12— Estimated number of trees on forest land by epiphyte loading (amounts of
nontree vegetation in the canopy and branches) and species (includes dead trees)
(continued)
Epiphyte loadings
Species
Hibiscus tiliaceus
Horsfieldia amklaal
Horsfieldia novo-guineensis
Horsfieldia palauensis
Horsfieldia sp.
Inocarpus fagifer
Intsia bijuga
Lumnitzera littorea
Macaranga carolinensis
Manilkara udoido
Manilkara zapota
Morinda citrifolia
Morinda latibracteata
Morinda pedunculata
Morinda sp.
Nephelium lappaceum
Osmoxylon oliveri
Osmoxylon sp.
Pandanus aimiriikensis
Pandanus dubius
Pandanus kanehirae
Pandanus tectorius
Pandanus utiyamai
Pangium edule
Parinari corymbosum
Parinari laurina
Parinari sp.
Pinanga insignis
Pithecellobium dulce
Pouteria calcarea
Pouteria obovata
Pouteria sp.
Premna obtusifolia
Pterocarpus indicus
Ptychosperma palauensis
Rhizophora apiculata
Rhizophora mucronata
Rhus taitensis
Rinorea carolinensis
Semecarpus venenosus
Sonneratia alba
Stemonurus ammui
Swietenia macrophylla
Swietenia mahagoni
48
None
Low
—
12,330
—
182,742
—
—
145,554
—
12,330
98,636
—
—
—
—
24,659
—
—
—
—
109,165
12,330
49,318
—
—
73,577
49,118
12,330
110,966
12,129
—
60,647
—
—
—
—
1,145,970
303,236
110,966
12,129
73,377
135,625
—
24,659
—
49,318
159,083
86,307
355,755
12,330
12,330
84,906
12,330
110,565
110,966
36,989
—
—
—
12,330
—
24,659
—
36,989
84,906
24,659
36,989
—
—
197,272
269,649
12,330
1,269,939
—
24,659
134,824
12,330
12,330
—
24,659
246,590
24,659
234,261
—
294,708
36,989
12,330
24,659
36,989
Moderate
Number of trees
—
49,118
98,636
282,178
—
—
—
—
36,788
36,989
24,659
24,659
36,989
—
—
—
—
24,659
24,659
12,129
24,659
12,330
—
12,330
172,613
123,295
—
505,510
—
12,330
109,365
—
36,989
—
61,648
—
49,318
61,648
—
135,425
—
—
—
24,659
High
All loadings
49,318
24,659
49,318
172,413
—
—
—
—
12,330
36,989
12,330
—
24,659
12,330
—
12,330
—
36,989
—
—
—
—
12,330
12,330
221,931
123,295
—
308,238
—
—
97,836
—
36,989
24,659
—
—
—
24,659
—
73,977
—
49,318
—
12,330
98,636
232,860
234,261
810,347
12,330
12,330
84,906
12,330
159,683
184,943
73,977
24,659
61,648
12,330
12,330
12,330
24,659
61,648
61,648
97,036
49,318
49,318
12,330
24,659
591,816
516,239
12,330
2,083,686
—
36,989
342,025
12,330
86,307
24,659
86,307
246,590
73,977
320,567
—
504,109
36,989
61,648
24,659
73,977
Palau’s Forest Resources, 2003
Table 12— Estimated number of trees on forest land by epiphyte loading (amounts of
nontree vegetation in the canopy and branches) and species (includes dead trees)
(continued)
Epiphyte loadings
Species
Symplocos racemosa
Terminalia catappa
Theobroma cacao
Timonius subauritus
Tournefortia argentea
Trichospermum ledermannii
Vitex cofassus
Xylocarpus granatum
Unknown
Unknown 0
Unknown 1
Unknown 3
Unknown 5
Unknown 10
Unknown 11
Unknown 30
Unknown, other
Total
None
Low
49,318
12,330
12,330
24,259
24,259
—
—
110,966
12,330
73,177
24,459
24,659
24,259
—
—
—
36,989
12,330
12,330
12,330
36,388
12,330
73,977
24,659
73,977
—
36,989
—
12,330
61,648
—
—
12,129
—
5,182,700
8,742,199
Moderate
Number of trees
—
—
36,989
48,518
12,330
24,659
24,659
—
—
12,330
12,330
12,330
—
12,330
12,330
—
36,989
4,794,504
High
All loadings
—
24,659
—
—
—
—
61,648
—
—
24,659
12,330
—
—
—
—
—
12,330
12,330
36,989
49,318
84,906
24,659
98,636
110,966
73,977
—
73,977
24,659
24,659
61,648
12,330
12,330
12,129
49,318
2,772,138
16,308,841
Comparing the inventory data from the present study to data from the MacLean
et al. (1988) timber inventory suggests that the trend of forest recovery and maturation continues on Palau. With the exceptions of forest loss owing to roads and urban
uses, forests appear to be maturing. On average, trees have been getting larger (fig.
16), and as they increased in size, some trees died during the “thinning phase”
(Oliver and Larson 1996) of forest succession. We found fewer stems per acre,
and greater basal area and volume per acre on forested field plots compared to the
MacLean et al. (1988) data (table 13). The MacLean et al. (1988) work was restricted
to forested lands on Babeldaob, whereas the current inventory included additional
forest types in limestone forest and the Rock Islands. Although our current sample
of plots in limestone forest was relatively small (11 out of 54 plots total), the 2003
data suggest much higher net wood volume in limestone (4,107 cubic feet per acre)
than in volcanic forests (2,424 cubic feet per acre). Much of the limestone forest is
in difficult terrain where access and human populations are limited. The limestone
forests were probably less impacted by agricultural development and thus are likely
to be in a later phase of maturity than their volcanic counterparts. Soil fertility may
also play a role in wood volume differences owing to less aluminum toxicity in
limestone versus the volcanic-derived soils.
49
RESOURCE BULLETIN PNW-RB-252
70
Percentage of all trees by diameter class
All trees (percent)
60
50
40
30
20
1985
2003
10
>2
9
7
27
–2
9
–2
5
25
–2
23
23
21
–
15
–1
7
17
–1
9
19
–2
1
.9
9.
–1
0.
9
11
.0
–1
2.
9
13
–1
5
–8
7.
0
5.
0–
6.
9
0
Diameter (inches)
Figure 16—The diameter distribution for the percentage of total trees measured on field plots appears to have
changed between the 1985 and 2003 inventories. Trees measured in the latest inventory were, on average,
larger than those measured in 1985, contributing to higher basal area and volume per acre values.
Table 13—Estimated number of trees per acre, basal area per
acre, net volume per acre, and standard errors (SE) for 1985 and
2003
Trees per acre
2
Basal area (ft per acre)
Volume (ft3 per acre)
50
1985
SE
2003
SE
1,282
136
102
—
856
146
68
—
1,740
188
2,744
296
Palau’s Forest Resources, 2003
Acknowledgments
The FIA Pacific Island inventories are the result of cooperative effort between
a number of groups and agencies. The USDA Forest Service, State and Private
Forestry in the Pacific Southwest Region has been a strong supporter of natural
resource assessments in the Pacific Islands. Many thanks to the Pacific Islands
Imagery Consortium partners for sharing costs on imagery and interpretation.
Thanks to Margie Falanruw with the Institute of Pacific Islands Forestry, Lynn
Raulerson at University of Guam, and Agnes Rinehart for species identification
and training; Lisa Fischer and Zhafeng Liu (Leo) at the Remote Sensing Lab in the
Pacific Southwest Region and Julie Anderson with PNW-FIA for imagery interpretation and mapping support; Pua Michael, Larry Mamis, Pamela Skilang, Dale
Baer, Falaniko Mika, Ritofu Lotovale for field assistance and logistical support. We
also thank Dale Weyermann, John Chase, Chuck Veneklase, and Ron Wanek with
FIA for GIS, programming, and technical support. Tom Cole, Robin DeMeo, Bob
Gavenda, and Tarita Holm offered very helpful comments on prior drafts.
Metric Equivalents
When you know:
Inches
Feet
Miles
Acres
Cubic feet
Tons
Tons per acre
Cubic feet per acre
Trees per acre
Degrees Fahrenheit
Multiply by:
2.54
.305
1.609
.405
.028
907
2.24
.07
2.471
(F - 32)/1.8
To find:
Centimeters
Meters
Kilometers
Hectares
Cubic meters
Kilograms
Tonnes or megagrams per hectare
Cubic meters per hectare
Trees per hectare
Degrees Celsius
Literature Cited
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Ngerekebesang, Koror, south Babeldaob, and Peleliu islands. Honolulu, HI:
International Archaeological Research Institute, Inc.
Climate Prediction Center. 2005. Composite rainfall of ENSO (El Niño/Southern
Oscillation) for Pacific Island stations. http://www.cpc.ncep.noaa.gov/pacdir/
ENSO11.shtml. (April 1).
Cochran, W.G. 1977. Sampling techniques. New York: John Wiley & Sons. 428 p.
51
RESOURCE BULLETIN PNW-RB-252
Cole, T.G.; Falanruw, M.C.; MacLean, C.D.; Whitesell, C.D.; Ambacher, A.H.
1987. Vegetation survey of the Republic of Palau. Resour. Bull. PSW-RB-22.
Berkeley, CA: U.S. Department of Agriculture, Forest Service, Pacific Southwest
Research Station. 13 p.
Endress, B.A.; Chinea, J.D. 2001. Landscape patterns of tropical forest recovery
in the Republic of Palau. Biotropica. 33: 555–565.
MacLean, C.D.; Cole, T.G.; Whitesell, C.D.; McDuffie, K.E. 1988. Timber
resources of Babelthuap, Republic of Palau. Resour. Bull. PSW-RB-23. Berkeley,
CA: U.S. Department of Agriculture, Forest Service, Pacific Southwest Research
Station. 8 p.
Mueller-Dombois, D.; Fosberg, F.R. 1998. Vegetation of the tropical Pacific
Islands. New York: Springer-Verlag. 733 p.
Oliver, C.D.; Larson, B.C. 1996. Forest stand dynamics. New York: Wiley. 520 p.
Parker, A.J. 1982. The topographic relative moisture index: an approach to soilmoisture assessment in mountain terrain. Physical Geography. 3: 160-168.
Smith, C.W.; Babik, N.R. 1988. Properties and management considerations of
some acid soils on the islands of Palau. In: Demeterio, J.L.; DeGuzman, B.,
eds. Management and utilization of acid soils of Oceania. Guam: University of
Guam: 39–61.
U.S. Department of Agriculture, Forest Service [USDA FS]. 2003. Field
instructions for the inventory of the Pacific Islands. Portland, OR: Pacific
Northwest Research Station, Forestry Sciences Laboratory, Forest Inventory
and Analysis. 256 p.
U.S. Department of Agriculture, Natural Resources Conservation Service.
1983. Soil survey of Islands of Palau, Republic of Palau. Washington, DC:
Soil Conservation Service. 120 p., 72 plates.
Western Regional Climate Center. 2004. Koror, Palau, period of record monthly
climate summary, 1953-2004. http://www.wrcc.dri.edu/cgi-bin/cliMAIN.
pl?pikoro. (September 12).
52
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