JouRNAL OF ]i ORES'l'R.Y, Vol. 56, No, 10, October 1958
Pmcha ed hy tlte ] ORES'J' SER-VICE Jor Oflieial Use
RetJri.ntcd from tho
How Much Douglas-Fir Will Grow on an Acre?
(known
as
the
Olympic
Forest
Diorama) is on exhibition in the
Hall of North American Forests of
the American Museum of Natural
Timber stands of 390,000 board
maximum possible number and vol­
feet per acre are rare, even in the
ume of trees. This acre (208.7 feet
virgin forests of the Pacific North­
square) lies at an elevation of 280
If cut, the stand would yield an
west.
fe13t on a level bench 90 feet above
estimated 30 percent of high-grade
However,
this
volume
of
History in New York City.
Douglas-fir (Pse t do ts ttga men­
Lake Quinault. The soil is a deep,
veneer logs 24 inches and larger in
ziesii) and western hemlock (Tsnga
heterophyllct) is growing on a
well-drained,
diameter.
annual temperature for the area is
las-firs
measured acre in the vVillaby Creek
approximately
from 46 to 78 inches, averaging 62
Recreational Area of the Olympic
monthly temperature varies from
inches.
National
a low of 40° in January to a hig·h
hemlock was 20 inches.
of 60° in July and .August.
statistics for the acre are given in
Forest,
vVashington.
near
Quinault,
'l'hough neither the
loamy sand.
50°
F. ;
Mean
average
Mean
oldest nor the largest of the spe­
annual precipitation is 125 inches,
cies, the trees are a striking display
with 30 inches falling during the
of vigor and height even in this
growing season (April-September).
reg·ion of tall, coniferous forests.
In 1948, W. E. Hiley and H. G.
Such abundant precipitation, good
Champion, while visiting the area,
climate are ideal for tree growth.
suggested that an exact record be
pro­
'l'he stand (Figs. 1 and 2) con­
sists of a Douglas-fir overstory with
ductivity of an acre of Douglas-fir.
a developing· understory of western
This record in turn might stimu­
late similar measurements for other
hemlock. All Douglas-firs are sound
and in vig·orous condition, although
principal forest types of the world.
height
made of the near-maximum
soil drainage, and moderate, humid
growth
has
apparently
As a result of their suggestion,
ceased. Boles are straight but not
an acre plot was laid out within
particularly smooth, and there are
no remnants of dead or down ma­
the densest part of the grove in
such a way as to encompass the
terial.
A
replica
FIG. I.-Uniformity in size and density are characteristic of
the Douglas-fir in this stand. The smaller understory trees a1·e
western hemlock, Note the carpet of Oregon oxalis in the
foreground.
of
this
area
at
Diameters of the Doug­
breast
height
ranged
Average diameter of the
Further
Table 1.
It is notable that the mean an­
nual increment for the acre-1,041
board feet-is 82 board feet more
than for a normal site I, 160-year­
old stancP Apparently, the stand
has maintained a high growth rate
throughout its life.
It should be clearly understood
that this example represents an ex­
treme case of high productivity.
1McArdle, Hichard E., W. H. Meyer,
and Donald Bruce. 'l'he yield of Douglas­
fir in the Pacific Northwest. ('l'able 9.)
U. S. Dept. Agric, Tech, Bul. 201, 74 pp.,
illus. Rev. 1949.
FIG. 2.-0lose spacing of the Douglas-fir is particularly strik·
ing, 'L'he prominent shrubby vegetation is whortleberry.
JOURNAL OF FORES'rRY
764
'l'ABLE l .
l
S AN D 8'l'A'l11S'l'IUS
-
' 1
li'Olt A
SELEC'l'ED ACRE 0111 0LD GR0"71l'H rri:hlBER IN 111HE
DOUGLAS-FIR TYPE, 0LYJ\IPIC NATIONAL FORES'l', .WASHINGTON
Douglas- fir
Item
Estimated stand age (years) -------------------­
Height of stand (feet)
Site -----------------------------------­
Stems (number)
Basal area (sq. ft.)
Volume:'
Cubic feet
Board feet (Scribner R.ule)
12
Mean annual increment:
Cubic feet -------------------­
Board feet (Scribner Rule)
__
________________________
-------------------­
_________________
-----------------------------------­
---------------------------------------------­
--------------­
Western hemlock
Total
150
100-175
28
58
59
714
49,625
371,820
3,155
18,370
52,780
390,190
132
992
8
49
140
1,041
ple may stimulate other foresters
1To convert cubic feet and boa1·d feet to cubic meters per hectare, multiply by 0.070
and 0.012, respectively.
"Western hemlock increment is computed on the same basis as Douglas- fi1· increment.
k::
few would show such volume at 375
years. It is hoped that this exam­
375
285
I
31
656
This fi
About
le Was
Th i s F .
crea te
i/e.
d by sc
Mis sc a
n s id e
antlin
g th e
ntifie
h owe
ver, sorn
e soft
ware h
e rni t
rnay
rern ai
n.
Other areas of greater volume may
exist in the Douglas-fir type, but
.n
d
:
.
to investigate and report the max­
innun acre yields of other forest
types in their areas.
NORMAN P. "'NORTHINGTON
P1tget Sonncl Resea1·ch Centet·,
Pac ific Northwest Forest and
Range Expet··iment Stat ion.
li'o1'est Set·vice,
U. S. Depa-rtment of Ag·ric1tltn1·e
PUblicatio .
n
en cor
rectec
t,: I