1069
Foliar chemical concentrations, growth, and site productivity relations in
western red cedar
M. A. RADWAN
Forestry Sciences Laboratory, Pacific Northwest Research Station, United States Department of Agriculture, Forest Service, 3625 93rd Avenue SW, Olympia, WA, U.S.A. 98502 AND CONSTANCE A. HARRINGTON Southern Forest Experiment Station, United States Department of Agriculture, Forest Service,
P.O. Box 3516, Monticello, AR, U.S.A. 71655
Received February 4, 1986 1 Accepted May 26, 1986 RADWAN, M. A., and C. A. HARRINGTON. 1986. Foliar chemical concentrations, growth, and site productivity relations in
western red cedar. Can. J. For. Res. 16: 1069-1075.
Important site and tree characteristics of western red cedar (Thuja plicata Donn ex D. Don) were examined in 19 natural stands
in the coastal and interior zones of western Washington and Oregon, U.S.A., and in western Vancouver Island, British
Columbia, Canada. The stands occurred at various elevations and on different soil types and differed in age, soil pH, and
associated plant species. Current-year foliage was collected during the winter and concentrations of N, P, K, S, Ca, Mg, Fe, Mn,
B, Zn, Cu, Mo, AI, and the chlorophylls were determined. Mean terminal growth during the previous 3 years and site index at
50 -year breast-height age were calculated for each stand. Site index ranged from 18 to 26 m. Terminal growth and foliar
concentrations of the macronutrients, micronutrients, AI, and the chlorophylls varied among the 19 sites and between the two
zones. Compared with known values for the most common associated conifers, foliar concentrations of red cedar were especially
low in Mn and Al and high in Ca and Mo. Site index was correlated positively with N, the chlorophylls, S, Cu, and B, and
negatively with Fe and AI. Also, N was positively correlated with the chlorophylls and with some of the other nutrients; there
were many correlations among the nutrients and between some nutrients and soil pH or stand age. The data obtained provide
base-line information for future analytical work with red cedar foliage. In addition, results suggest that (i) nutrient management
strategies in western red cedar stands may differ from those for other conifers and different strategies may be necessary for the
coastal and interior zones, (ii) productivity of red cedar may be improved by cultural treatments, including fertilization, which
would enhance levels of chlorophyll as well as some essential elements (N, S, P, B, and Mo) in the foliage, (iii) levels of some
chemicals in the foliage, such as N, chlorophyll, S, and B, may be useful as indicators to assess site quality for red cedar
production, and (tv) chlorophyll may be used as a simple means to estimate N status of red cedar.
RADWAN, M. A., et C. A. HARRINGTON. 1986. Foliar chemical concentrations, growth, and site productivity relations in
western red cedar. Can. J. For. Res. 16: 1069-1075.
Les auteurs ont examine des caracteristiques importantes des stations et des arbres du cectre de l'ouest (Thuja pUcata Donn
ex D. Don) dans 19 peuplements naturels des zones c6tiere et interieure de l'ouest des etats de Washington et d'Oregon,
Etats-Unis, et de l'ouest de l'lle de Vancouver, C.-B., Canada. Les peuplements se situaient a diverses altitudes, ils etaient
associes a des sols differents et ils variaient quant a l'age, au pH du sol et a la vegetation associee. On a echantillonne Ie
feuillage au cours de l'hiver et on a mesure les concentrations en N, P, K, S, Ca, Mg, Fe, Mn, B, Zn, Cu, Mo, Al et la
teneur en chlorophylle. Pour chaque peuplement, on a calcule la croissance terminale moyenne des trois annees precedentes et
l'indice de qualite de station a 50 ans. Ce dernier variait de 18 it 26 m. On a observe une variation des concentrations foliaires
en elements et en chiorophylles entre les 19 stations et entre les deux zones. Par comparaison avec des valeurs connues pour
les coniferes associes les plus communs, les concentrations en Mn et Al etaient tres faibles et les concentrations en Ca et Mo
etaient elevees. L'indice de qualite de station etait correJe positivement avec N, les chlorophylles, S, Cu et B, et negativement
avec Fe et AI. De meme, N etait correle positivement avec les chiorophylles et avec certains autres elements. Les donnees
fournissent une information de base pour des analyses futures du feuillage du coore de I'ouest. De plus, les resultats suggerent
que (i) : les strategies d'amenagement de la fertilite dans les peuplements de cectre de I 'ouest peuvent differer de celles qui sont
utilisees pour les autres coniferes, et differentes strategies peuvent etre necessaires pour les zones c6tiere et interieure; (ii) la
productivite du cectre peut etre amelioree par des traitements culturaux, incluant la fertilisation, capables d'augmenter la teneur
en chlorophylle et en elements essentiels (N, S, P, B et Mo) du feuillage; (iii) les niveaux de certains constituants du feuillage
tels que N, la chlorophylle, S et B peuvent servir d'indicateur utiles de la qualite de station pour la production du coore de
l'ouest; et (iv) Ja chlorophylle peut etre utilisee comme moyen simple d'estimer Ie statut azote du coore de l'ouest.
[Traduit par la revue]
Introduction Western red cedar (Thuja pUcata Donn ex D. Don) is an
important softwood species in the forests of northwestern North
America. Its range extends from southeastern Alaska to
northern California and eastward to Idaho, Montana, and
eastern British Columbia (Fowells 1965). In the United States,
more than 50% of the red cedar is in western Washington and
IRevised manuscript received May 20 , 1986.
Printed in Canada
Oregon (Bolsinger 1979); in Canada, the greatest concentration
of the species is found in coastal British Columbia. Red cedar
occurs most commonly in mixed stands. The most common asso­
ciated conifers in western Washington, Oregon, and British
Columbia are Douglas-fir (Pseudotsuga menziesii (Mirb. )
Franco) and western hemlock (Tsuga heterophylla (Raf. )
Sarg.).
Western red cedar is a specialty wood with high natural
durability. Demand for and prices of red cedar products have
CAN. 1. FOR. RES. VOL. 16, 1986
1070
increased rapidly over the past decade. In the United States, the
annual cut in recent years has been about twice the net annual
growth (Bolsinger 1979) and the red cedar resource is being
depleted. Management of existing young-growth stands could
result in increased growth rates and help stretch the resource,
Prescribing effective management practices, however, requires
basic information on the biology and nutrition of the species. To
date very little work has been done. Only a few reports deal with
the foliar nutrient content of trees in natural stands (Gessel et al.
1950; Tarrant et al. 1951; Warren et al. 1952; Ovington 1956;
Beaton, Moss et ai, 1965; Imper and Zobel 1983; Harrington
and Wierman 1985) or young seedlings in the greenhouse or
nursery (Walker et al. 1955; Smith et al. 1968). Most
publications dealt with very few samples and reported levels of
only a few essential elements, Furthermore, the literature does
not contain any data on relationships between the different
chemical components in the foliage or between site index or
height growth and important foliar constituents.
This study was designed to assess site quality, height growth,
and foliar chemical composition of red cedar from sites of
different productivity in the western portion of the species'
range. In addition to the nutrients, foliar aluminum (AI) and the
chlorophylls were also determined. Aluminum was included
because of its potential phytotoxic effects, especially on wet
sites. Chlorophylls have recently been shown to be correlated
with growth, site index, and (or) foliar nitrogen (N) content of
other conifers (Viro 1965; Heinze and Fiedler 1976; Radwan
and DeBell 1980).
British Columbia
Canada
United States
13
0
0
14
II
12
0
Olympia
Washington
016
o
17
•
Portland
Oregon
Materials and methods
The sites
Nineteen natural stands of western red cedar located in western
Washington and western Oregon, U.S.A., and western Vancouver
Island, British Columbia, Canada, were selected for investigation.
Eight sites were in the coastal zone within 20 km of the Pacific Coast
and 11 sites were in the interior of western Washington and Oregon,
7S-1S0 km from the coast (Fig. 1 ). Sites were selected to assure
representation of a wide range of soil and site conditions. Stand age
ranged from 18 to 34 years. Each stand had an area of at least O.S ha
where topography and stand structure were fairly uniform and red cedar
was at least 20 % of the basal area.
At each site, 10 dominant or codominant trees were randomly
selected for study. All trees appeared healthy with no evidence of
previous top damage.
Estimation of site index
At each site, test trees were felled during the 1981 -1 982 dormant
season. Tree heights and ages were determined and site index at
50 -year breast-height age was estimated from Kurucz's (1978 ) tables.
Height growth measurements
Stem tenninals with more than 3 years' growth were brought to the
laboratory where they were cut back to the point where the last 3 years
of growth had started. This was determined by counting the rings of the
stem cross sections under magnification, Terminal growth was mea­
sured and average height growth per year for the 3 years immediately
before harvest was computed.
Sampling and pH determination of mineral soil
Soil samples, to a depth of 20 cm, were collected beneath the test
trees after the forest floor was removed. Each sample consisted of
material obtained from two or three randomly selected spots at
distances of 0.S-2.0 m from each test tree. Samples of each site were
composited, thoroughly mixed, air dried at room temperature, and
passed through a 2-mm sieve. Soil pH was determined on 1: 1 mixtures
with water using a glass electrode,
·Corvallis
0 18
o
18
FIG. I. Approximate geographic location of study sites in the
Pacific Northwest. Sites 1 -8 (.) occur in the coastal zone within 20 km
from the Pacific Coast; sites 9-19 (0) are located in the interior of
western Washington and Oregon, 7 S-150 km from the coast. Site
descriptions are in Table I.
Sampling and chemical analysis of foliage
Immediately after felling, one composite sample of about 200 g of
fresh foliage was collected from all 10 test trees at each site. Samples
were obtained from all sides of the trees and sampling was limited to
vigorous branches in the sunlit part of the crown, Samples consisted of
the current year's growth of secondary lateral branchlets with their
scalelike leaves. Current-year growth was identified by its terminal
position on the branches and by its lighter color upon examination of
the underside (Fig. 2 ). Samples were individually placed in cold jars
and transported to the laboratory in a portable cooler.
In the laboratory, staminate and ovulate flower buds, if present , were
discarded. Subsamples of the fresh leaves were taken for estimation of
moisture and chlorophyll contents. Remaining foliage was dried to
constant weight at 6SOC, ground to 40 mesh in a stainless steel Wiley
mill, and stored in closed jars until it was analyzed.
Moisture content was determined by drying the foliage to constant
weight at 65°C. The chlorophylls were extracted from the leaves with
80% acetone, optical densities of the extracts were measured, and
contents were computed according to Amon (1949). Other foliar
analyses were carried out as follows: total N (including nitrate) by the
micro-Kjeldahl procedure (Bremner and Mulvaney 1982); phosphorus
(P) by the molybdenum blue technique (Chapman and Pratt /961) ;
RADWAN AND HARRINGTON
1071
the interior than on the coast (Table 2). Also, as expected, levels
of chl-a were consistently higher than those of chi-b. The
chl-a:chl-b ratio was somewhat lower in the interior than on the
coast. The average ratio of 2.7 is similar to that found in
Pinus
spp. (Kramer and Kozlowski 1960) but lower than that reported
for western hemlock (Radwan and DeBell 1980).
For all sites combined, levels of chi-a, chl-b, and t-chl were
each significantly correlated with site index, terminal growth,
and total N in the foliage (Table 3). This is not surprising since N
is part of the chlorophyll molecule and foliar N levels were
b
d
related to site index and terminal growth (Table 3). These
correlations are similar to results obtained earlier with other
forest tree species (Viro 1965; Heinze and Fiedler 1976;
Radwan and DeBell 1980).
Total N
Foliar N concentrations ranged from 0.88 to 1.54% (Table 4).
Average total N (1.20%) was within the deficiency levels
«1.5%) for red cedar seedlings (Walker
et al. 1955). For most
study sites, therefore, growth of red cedar would likely benefit
from application of N fertilizer. Success of such treatment has
been recently demonstrated in a thinned stand of red cedar in
[.
FIG. 2. Diagram of the upper part of a branch of western red cedar
illustrating (a) previous year's growth, ( b) current year's growth, (c)
branchlet, and (d) foliage taken for analysis.
sulfur (S) by the turbidimetric method of Butters and Chenery (1959);
potassium (K), calcium (Ca), magnesium (Mg), iron (Fe), manganese
(Mn). zinc (Zn), and copper (Cu) by standard atomic absorption
techniques (Perkin-Elmer Corporation 1976); molybdenum (Mo) by
the thiocyanate colorimetric method (Chapman and Pratt 1961); and
boron (B) by the quinalizarin procedure (Horwitz 1980).
Statistical analysis
coastal Washington (Harrington and Wierman 1985).
For all sites, total N was significantly correlated with many of
the variables determined, in addition to site index, terminal
growth, and the chlorophylls (Table 3). Foliar nutrients cor­
related with N included S, P, Mg, Cu, and B (Table 5).
Strongest correlations were with S
(r
=
0.90) and P
(r
=
0.73).
Sulfur is essential for the synthesis of S-containing amino acids
and P is especially important to N nutrition through its key role
in energy metabolism (Bonner and Varner 1965).
Macronutrients other than N
Foliar concentrations of P, K, Ca, Mg, and S were consis­
(p < 0.01) in the interior than on the coast (Table
4). In this respect, red cedar is similar to western hemlock
tently higher
(Radwan and DeBell 1980). Mineral soils from the interior sites
contain higher concentrations of extractable mineral nutrients
Correlation coefficients (r) between the variables measured were
calculated for all sites combined and separately for each of the two
geographical zones (Snedecor 1961). Mean values for the two
geographical zones were compared with at-test (Snedecor 1961).
Differences between individual sites could not be statistically tested
because observations were made on subsamples; no replication was
possible at the different sites.
than do soils from coastal sites (unpublished data on file at the
Results and discussion
(e.g., Beaton, Moss et al. 1965; Harrington and Wierman
1985). Many coastal soils are known to be especially low in
The sites
The sites studied varied in many physical, soil, and plant
properties (Table 1). Average elevation was highest in the
interior zone. The sites represented 17 soil series. Average pH
was lower
(p < 0.01) on the coast than in the interior. Average
site index for the coastal sites was not significantly different
from that for the sites in the interior zone. Terminal growth for
the 3 years immediately before harvest ranged from 30 to 65
cm/year. Terminal growth was higher (p < 0.01) in the interior
than in the coastal zone. For all sites, the average growth was 52
cm/year and terminal growth was correlated with site index
(r = 0.64, p < 0.01). A similar correlation was obtained with
hemlock (Radwan and DeBell 1980).
U.S. Department of Agriculture, Forest Service, Forestry
Sciences Laboratory, Olympia, WA) and this is reflected in the
composition of the foliage.
Phosphorus concentrations were especially high in the
interior (0.28%). Average P for the coast (0.16%), however,
was within the range of values in the literature for red cedar
extractable P (Radwan and Shumway 1983). Correlations with
other mineral nutrients indicate that for all sites, P was strongly
related to K, Mg, and S (Table 5).
As expected, Ca concentrations were high (0.58-0.90%)
relative to important associated conifers such as Douglas-fir
(0.25-0.50%; Beaton, Moss
et ai. 1965; Lavender and Carmi­
chael 1966; Zobel and Hawk 1980) and western hemlock
(0.18-0.50%; Beaton, Moss
et ai. 1965; van den Driessche
1976; Radwan and DeBell 1980; Zobel and Hawk 1980). Our
values, however, are not as high as some of those reported in the
literature for red cedar (1.14-1.98%; Gessel
et al. 1950; Imper
and Zobel 1983). This discrepancy, we believe, is due to
differences in methods of sampling the foliage. Unlike others,
we sampled only current-year growth of secondary branchlets.
The chiorophylls
Concentrations of chlorophyll a (chi-a), chlorophyll b
Samples of others included "two or three years growth" (Gessel
(p < 0.01) in
et al. 1950) or consisted of the "apica1 2 dm" tissue that included
(chi-b), and total chlorophyll (t-chl) were higher
CAN. J. FOR. RES, VOL. 16. 1986
1072
TABLE 1.
Site No.
and general
location
Stand
age
(years)
Site
index at
50 years
(m)
Tenninal
growth
per year
(cm)
Characteristics of western red cedar sites
Elevation
(m)
Soil
pH
Soil
series
Associated plant speciesQ
Coastal zone
1
30
17.8
30
5
4.5
2
28
22.7
38
15
5.2
3
19
24.1
56
75
4.4
4
23.1
46
19.3
44
8
10
4.2
5
30
26
6
28
22.8
44
2
4,5
7
28
21.3
44
2
4.0
8
27
24.0
54
6
27x
21.9x
44x
Averageb
15x
4.0
4.6
Reeses
Kootowis
Kydaka
Kydaka
Tealwhit
H albert
Hoko
Knappton
Hemlock,
Hemlock,
Hemlock,
Hemlock,
Hemlock,
Hemlock,
Hemlock,
Hemlock,
Crinker
Olomount
Elwell
Playco
Bunker
Lates
Bromo
Swift
Swift
Carpenter
Frissell
Douglas-fir, hemlock, salal
Hemlock, fern, devil's club, salmonberry
Douglas-fir, hemlock
Hemlock, Douglas-fir, silver fir, Oregon grape, fern
Douglas-fir, vine maple, salal, devil's club
Douglas-fir, vine maple, salal, devil's club
Hemlock, Douglas-fir, yew, Oregon grape
Douglas-fir, noble fir, blackberry
Pine, noble fir, hemlock, salal
Douglas-fir, hemlock, vine maple, fireweed
Douglas-fir, big-leaf maple, fern, blackberry
pine, sala!, huckleberry
pine, salal, huckleberry
alder, salal, huckleberry
alder, salal, huckleberry
spruce, salal, huckleberry
Douglas-fir, pine, salal, huckleberry
Douglas-fir, pine, salal
alder, salal
4.4x
Interior zone
9
19
27.0
64
1200
10
21
25.7
63
625
5.1
4.7
11
34
31
23.8
65
925
4.8
12
17.7
46
1025
5.2
13
29
24.4
53
350
5.3
14
28
24.9
58
600
5.2
15
26
22.8
64
875
5.3
16
19
22.8
58
900
5.4
17
24
19.1
57
875
5.3
18
18
24.8
60
875
5.8
19
24
25.2
52
750
5.7
25x
23.5x
58y
818y
5.2y
Averageb
"Hemlock, Tsuga heterophylla; pine, Pinus m Oil/le ola ; salal. Gaultheria shallon; huckleberry, Vaccillium parvifolium; alder. Alnus rubra; spruce. Picea s;lehells;s; Douglas-fir.
Pseudotsuga menziesii; fern. Polys/iellum munilwn; devil's club. Oplopanax horridum; salmonberry, Rubus speetabilis; silver fir. Abies amabilis; Oregon grape, Berberis
aquifolium; vine maple. Acer circinawm; yew, Taxus brevifolia; noble fir. Abies procera; blackberry. Rubus 'lTsinlls; fireweed. Epi/obium allguslifolium; big-leaf maple.
Acer macrophyllum.
bAverage values in the same vertical column followed by the same letter are not statistically different at p < 0,05.
TABLE 2. Chlorophyll levels in western red cedar foliage
Site No,
and general
location
Chlorophyll
Chlorophyll
a
b
(mg/g)
(mg/g)
Total
chlorophyll
(mg/g)
Coastal zone
1
1.22
0.44
1.66
2
1.50
0,55
2.05
3
1.48
0.49
1.97
4
1.42
0.44
1.86
1.48
5
1.10
0.38
6
1.44
0.50
1.94
7
1.58
0.58
2,16
8
1.50
0.56
2.06
1.41x
0.49x
1.90x
2.55
Averagea
Interior zone
9
1.78
0.77
10
2.42
1.04
3.46
11
2.04
0.81
2.85
12
1.16
0.43
1.59
13
2.52
0.86
3.38
14
2.30
0.86
3.16
15
1.86
0.66
2.52
16
17
2,23
0.78
3.01
1.85
0.66
2.51
18
1.90
0.82
2.72
19
1.60
0_65
2.25
1.97y
0.76y
2.73y
Averagea QAverage values in the same vertical column followed by different letters are statistically
different at p < 0.01, "some fine, brittle branchlets" (Imper and Zobel 1983). Such
sampling elevates the results of the Ca content because Ca
accumulates in older foliage and woody tissues.
With one minor exception (Ca vs. S in the interior), Ca
concentrations were not correlated with concentrations of other
elements. In addition, all macronutrients except Ca were
positively related to tenninal growth (Table 6), The poor
relationships between Ca and other variables may be indirect
evidence that red cedar accumulates Ca in excess of its nutrient
needs.
Concentrations of K, Mg, and S were within the range of
published values for red cedar trees (e.g., Ovington 1956;
Beaton, Moss et at. 1965; Imper and Zobel 1983; Harrington
and Wiennan 1985); some values, however, especially in the
coastal zone, were within the deficiency levels for seedlings
(Walker et at. 1955).
Concentrations of P, K, Mg, and S in red cedar were within
the ranges of values reported for western hemlock and Douglasfir (e. g., Beaton, Moss et al. 1965; Lavender and Carmichael
1966; van den Driessche 1976; Radwan and DeBell 1980; Zobel
and Hawk 1980; Radwan et at. 1984).
For all sites, there were strong correlations between K and S,
K and Mo, Mg and Zn, and S and Cu (Table 5),
Micronutrients and aluminum
Concentrations of the microelements B, Zn, Cu, and Mo
were higher (p < 0.05) in the interior than on the coast. The
largest difference between the two zones was for Mo (0.21 vs.
0,05 ppm) (Table 7). This may be related to differences between
1073
RADWAN AND HARRINGTON
TABLE
3. Correlations between nitrogen, site index,
tenninal growth, and chlorophyII for western red cedar
TABLE
5. Significant correlations (p < 0.05 ) between elemental
concentrations in western red cedar foliage
Significant correlations by element pai
Correlation coefficienta (r)
Characteristics being
compared
All
sites
0.77**
0.77**
0.78**
0.73*
0.56
0.69
0.60*
0.62*
0.62*
Site index versus:
nitrogen
chlorophyll a
chlorophyll b
total chlorophyll
0.60**
0.58**
0.65**
0.61**
0.81*
0.75*
0.5 3
0.70
0.43
0.51
0.73*
0.59
Terminal growth versus:
nitrogen
chlorophyll a
chlorophyll b
total chlorophyll
0.71**
0.67**
0.73**
0.70**
0.69
0.42
0.23
0.37
0.39
0.43
0.59
0.49
0.05; .'. P
Element P
Interior
sites
Nitrogen versus:
chlorophyll a
chlorophyII b
total chlorophyll
"Level of statistical significance: '. p <
TABLE
Coastal
sites
<
N
P
K
S
Ca
Mg
Fe
Mn
B
Zn
Cu
Mo
ACI
AC A
AC
A
A
I
A
£;.
C
C
B
Zn Cu Mo Al
AC A
AC
A
A
A
A
AI
A
A
AI
AI
C
A
AI
A
A I
AI £.
AC
A
A
A
"The symbols A. C, and I indicate significance of the correlation coefficient (r) for
relations are underlined.
0.01.
P
K
Ca
Mg
S
Averagea
0.90
1.10
1.20
1.15
0.88
0.92
1.08
1.22
1.06x
0.15
0.16
0.21
0.17
0.14
0.12
0.15
0.15
0.16x
0.47
0.51
0.60
0.46
0.36
0.46
0.52
0.47
0.48x
0.60
0.80
0.58
0.60
0.67
0.64
0.61
0.79
0.66x
0.12
0.11
0.14
0.14
0.14
0.12
0.11
0.13
0.13x
0.09
0.10
0.10
0.09
0.08
0.09
0.09
0.10
0.09x
Interior zone
9
10
11
12
13
14
15
16
17
18
19
Averagea
1.48
1.5 3
1.28
1.21
1.38
1.54
1.25
1.32
L12
1.13
1.00
1.29y
0.29
0.32
0.30
0.28
0.24
0.32
0.30
0.25
0.24
0.30
0.26
0.28y
1.05
0.86
0.63
0.88
0.60
0.72
0.82
0.66
0.86
1.12
0.92
0.83y
0.62
0.68
0.74
0.72
0.90
0.70
0.82
0.78
0.73
0.74
0.90
0.76y
0.14
0.16
0.14
0.15
0.16
0.17
0.18
0.14
0. l 3
0.14
0.15
0.15y
0.13
0.13
0.10
0.10
0.11
0.12
0.11
0.11
0.10
0.11
0.09
O. l ly
Coastal zone
I
Ca Mg Fe Mn
all sites combined (A). coastal sites only (C). or interior sites only (I). Negative cor­
N
2
3
4
5
6
7
8
S
AI
4. Macronutrient concentrations (%) in western red cedar
foliage
Site No.
and general
location
A
K
"Average values in the same vertical column followed by different letters are statistically
different at p < 0.01.
the zones in soil pH (Table 1); Mo availability is known to
decrease with increased soil acidity (Mortvedt et al. 1972).
Literature on the rnicronutrients and Al in red cedar is
extremely limited and available values cannot be compared with
our data. Such values are from very few analyses for (i) Fe and B
in very young seedlings grown with nutrient solution in a
greenhouse (Gessel et al. 1950), (ii) Fe and Mn in foliage of
2 1-year-old trees from Great Britain, with possible contamina-
tion with Fe "in the process of grinding" (Ovington 1956), and
(iiO Cu and Zn in two samples of un aged red cedar from an
unnamed location in the Pacific Northwest for a prospecting
survey (Warren et al. 1952).
Compared with important associated conifers, red cedar
concentrations of Mn (69-383 ppm) and Al ( 12-86 ppm) were
lower and those of Mo, especially in the interior (0.03-0.52
ppm), were higher than those reported for western hemlock
(Mn, 530-2000 ppm; AI, 550-1000 ppm; Mo, 0.0 1-0.05 ppm)
and Douglas-fir (Mn, 270-1370 ppm; AI, 70-5OOppm; Mo,
0.05-0.lOppm) (Beaton, Brown et al. 1965; Radwan and
DeBell 1980; Zobel and Hawk 1980). The low concentrations of
Al and the high levels of Mo were surprising. Many of the soils
at the coastal sites were poorly drained and Al is usually present
in higher concentrations in forest trees growing on relatively wet
sites. On the other hand, Mo levels appear to be the highest
reported, so far, for a Pacific Northwest conifer.
Foliar levels of B, Fe, Zn, and Cu in red cedar were within the
ranges of values reported for western hemlock and Douglas-fir
(e.g., Beaton, Brown et al. 1965; Radwan and DeBell 1980;
Zobel and Hawk 1980).
Effect of soil pH and stand age on foliar nutrients
As expected, foliar nutrient concentrations in red cedar varied
with soil pH and stand age (Table 6). Correlations of nutrients
with pH were all positive. Soil pH is known to influence nutrient
availability (Pritchett 1979), which can, in turn, affect nutrient
levels in the foliage. In contrast, significant correlations with
stand age were all negative. Reductions in nutrient requirements
with age may explain this relationship (Miller et al. 1981).
Foliar nutrients, site index, and terminal growth relationships
Site index and terminal growth were significantly correlated
with many foliar elements (Tables 3 and 6). These correlations
suggest that some elements, such as N and S, may be useful as
indicators to assess site quality for red cedar production (i.e.,
higher concentrations associated with better sites).
Differences in relationships between study variables
Correlations among the variables studied were calculated for
all sites as well as for each geographical zone. Resulting
CAN.
1074
TABLE
J. FOR. RES.
6. Significant correlation coefficients
V OL .
(r)
16, 1986
between stand and site characteristics
and elemental concentrations in western red cedar foliage, all sites combinedG
Soil pH
Stand age
r
Element
Terminal growth
Site index
Element
r
P
K
Ca
S
Mo
0.66**
K
-0.53*
S
0.74**
S
-0.46*
Fe
0.70**
Cu
-0.51*
B
0.56*
0.46*
Mo
-0.69**
Cu
Al
0.50*
Element
0.66**
r
Element
r
P
K
Mg
S
B
Zn
Cu
Mo
0.79**
0.61**
-0.51*
-0.49*
·Correlations between N and terminal growth, and N and site index are in Table
significance: *, p <
TABLE
0.05;
"
. P < 0.0 I.
red cedar 1.1
Site No.
o/"
0.9
Fe
Mn
B
Zn
Cu
Mo
AI Coastal zone 1
82
166
13
16
4
0.06
50
2
3
54
143
18
20
5
0.10
37
37
383
26
6
0.06
12
4
39
183
22
17
23
5
0.02
25
5
83
94
16
8
0.06
86
6
7
56
69
16
22
13
7
0.05
36
122
20
20
5
0.02
122
18
22
5
0.04
12
38
160x
18x
20x
6x
0.05x
37x
12
AverageO
0.69**
0.53*
0.63**
0.64**
0.46*
"
"
/
0.32
"
44
39
54x
"=0.86
0
"
/r=0.87
/
/
;; 0.7
o "/
0
C'J'/
/
"
-
9
53
145
32
10
9
0.36
138
22
25
29
71
0.26
25 11
42
368
20
30
7
0.08
18
12
64
64
52
50
132
108
24
27
6
0.12
37
24
37
8
0.05
62
234
24
24
10
0.03
24
13
14
15
16
181
21
48
6
0.14
37
162
18
24
9
0.20
25
196
14
21
7
0.24
49
17
44
62
18
50
102
20
24
9
0.52
37
19
48
110
22
22
6
0.32
54x
170x
21y
29y
8y
0.21y
37
33x
Averagea
"Average values in the same vertical column followed by the Same letter are not
statistically different at p <
0.05.
correlation coefficients (r) show much variation between values
for all sites, the coast, and the interior for each set of correlations
(Tables 3 and 5). Only correlations between chl-a and N and
between N and S were significant for all three data sets.
Remaining correlations were significant only for one or two of
the three data sets. A narrow range of values in one geographical
zone may be the cause of the lack of significant correlation in
that zone; this is illustrated by the relationship between K and
Mo (Fig. 3A). Other examples of the significant correlations
present are (i) P and Mn correlated on the coast but not in the
interior (Fig. 3B), (ii) chl-b and site index correlated in the
interior but not on the coast (Fig. 3C), and (iii) P and terminal
growth correlated in the interior and on the coast combined but
not in either zone (Fig. 3D).
0
0
0
o
0
0
0
0
'iP
a.
0
0
0
0.25
0.20
..
0.3,
,
0.02 0.1
28
!
0.2
!
0.3
,
0.5
!
0.4
f= 0.96
0.14
70
Mo(ppm) !
140
I
210
I
280
Mn(ppm)
C
o
60
Interior zone
10
B
0.29
/
and general
8
0.62**
Level of statistical
A
7. Concentrations (ppm) of microelements in foliage of western location
3.
0.62**
50
'"
.
S
40
E
18
.
..--l..---.I
0.28 0.49 0.63
Chlorophyll
•
0.84
b
!
1.05
(mg/g)
iP .L2- -= :"'- -'-L --' "-'. ""' ---=0-=.S 2
0 24
1
0 .18
P (%)
FIG. 3. Relationship between selected study variables, illustrating
(0) zones. The best linear
(_. -), and interior
sites when
differences between coastal (.) and interior
fit line was drawn for all (---), coastal
the correlation coefficient was significant at p < 0.05.
Conclusions
Results, especially the foliar chemical data, indicate impor­
tant differences between red cedar in the interior and on the
coast and between the species and other important associated
conifers. Different management strategies, therefore, may be
indicated for red cedar compared with those for other conifers,
and for the species in different geographical zones of its natural
range.
The various correlations between the numerous variables
studied suggest that (i) productivity of red cedar may be
improved by cultural treatments, including fertilization, which
would enhance levels of chlorophyll as well as some essential
elements (N, S, P, B, and Mo) in the foliage, (ii) levels of some
chemical elements or compounds in the foliage, such as N,
RADW AN AND HARRINGTON
chlorophyll, S, and B, may be useful as indicators to assess site
quality for red cedar production, and
(iii) chlorophyll may be
used as a simple means of estimating the N status of red cedar.
Acknowledgements
The authors thank the following organizations for their
cooperation in this study: ITT Rayonier, Inc., MacMillan
Bloedel Limited (Canada), Murray Pacific Corp., Washington
State Department of Natural Resources, and the Pacific North­
west Region of the U.S. Department of Agriculture, Forest
Service. The authors also thank J. M. Kraft, J. E. Wilcox, D.
W. Johnson, and H. M. Culliton, Forestry Sciences Laboratory,
Olympia, W A, for their valuable assistance with the various
phases of the study.
ARNON, D. I. 1949. Copper enzymes in isolated chloroplasts.
Polyphenoloxidase in Beta vulgaris. Plant Physiol. 24: 1-15.
BEATON, J. D. , G. BROWN, R. C. SPEER, I. MACRAE, W. P. T.
McGHEE, A. Moss, and R. KOSICK. 1965. Concentration of
micronutrients in foliage of three coniferous tree species in British
Columbia. Soil Sci. Soc. Am. Proc. 29: 299-302.
BEATON, J. D. , A. Moss, I. MACRAE, J. W. KONKIN, W. P. T.
MCGHEE, and R. KOSICK. 1965. Observations on foliage nutrient
content of several coniferous tree species in British Columbia. For.
Chron. 41: 221-236.
BOLSINGER, C. L. 1979. Western red cedar-a forest resource in
transition. U.S. For. Servo Resour. Bull. PNW-85.
BONNER, 1., and J. E. VARNER (Editors). 1965. Plant biochemistry.
Academic Press, New York.
BREMNER, J. M., and C. S. MULVANEY. 1982. Nitrogen-total. In
Methods of soil analysis. Part 2. Agronomy, No. 9. pp. 595-624.
BUTTERS, B., and E. M. CHENERY. 1959. A rapid method for the
determination of total sulphur in soils and plants. Analyst (London),
84: 239-245.
CHAPMAN, H. D. , and P. F. PRATT. 1961. Methods of analysis for
soils, plants, and waters. Division of Agricultural Science, Univer­
sity of California, Berkeley, CA.
FOWELLS, H. A. (Compiler). 1965. Silvics of forest trees of the United
States. Agric. Handb. (U.S. Dep. Agric., Sci. Educ. Adm.), No.
271. pp. 686-691.
GESSEL, S. P. , R. B. WALKER, and P. G. HADDOCK. 1950. Preliminary
report on mineral deficiencies in Douglas-fir and western red cedar.
Soil Sci. Soc. Am. Proc. 15: 364-369.
HARRINGTON, C. A. , and C. A. WIERMAN. 1985. Response of a
poor-site western red cedar stand to precommercial thinning and
fertilization. U.S. For. Servo Res. Pap. PNW-339.
HEINZE, M., and H. J. FIEDLER. 1976. Correlations between chloro­
phyll content and site factors, nutritive conditions as well as growth
of conifers. Flora (Jena), 165: 269-293.
HORWITZ, W. (Editor). 1980. Official methods of analysis of the
Association of Official Analytical Chemists. Association of Official
Analytical Chemists, Washington, DC.
IMPER, D. K., and D. B. ZOBEL. 1983. Soils and foliar nutrient analysis
of Chamaecyparis lawsoniana and Thuja plicata in southwestern
Oregon. Can. J. For. Res. 13: 1219-1227.
1075
KRAMER, P. J., and T. T. KOZLOWSKI. 1960. Physiology of trees.
McGraw-Hili, Inc., Hightstown, NJ.
KURUCZ, J. F. 1978. Preliminary polymorphic site index curves for
western red cedar, Thuja plicata Donn. , in coastal British Columbia.
MacMillan Bloedel Ltd., Res. Note 3.
LAVENDER, D. P., and R. L. CARMICHAEL. 1966. Effect of three
variables on mineral concentrations in Douglas-fir needles. For. Sci.
12: 441-446.
MILLER, H. G., 1. D. MILLER, and J. M. COOPER. 1981. Optimum
foliar nitrogen concentrations in pine and its change with stand age.
Can. J. For. Res. 11: 563-572.
MORTVEDT, J. J. , P. M. GIORDANO, and W. L. LINDSAY (Editors) .
1972. Micronutrients in agriculture. Soil Science Society of
America, Madison, WI.
OVINGTON, J. D. 1956. The composition of tree leaves. Forestry, 29:
22-28.
PERKIN-ELMER CORPORATION. 1976. Analytical methods of atomic
absorption spectrophotometry. Perkin-Elmer Corp. , Norwalk, C:T.
PRITCHETT, W. L. 1979. Properties and management of forest soils.
John Wiley and Sons, New York.
RADWAN, M. A., and D. S. DEBELL. 1980. Site index, growth, and
foliar chemical composition of western hemlock. For. Sci. 26:
283-290.
RADWAN, M. A. , D. S. DEBELL, S. R. WEBSTER, and S. P. GESSEL.
1984. Different nitrogen sources for fertilizing western hemlock in
western Washington. Can. 1. For. Res. 14: 155-162.
RADWAN, M. A., and 1. S. SHUMWAY. 1983. Soil nitrogen, sulfur, and
phosphorus in relation to growth response of western hemlock to
nitrogen fertilization. For. Sci. 29: 469-477.
SMITH, 1. H. G. , J. WALTERS, and A. KOZAK. 1968. Influences of
fertilizers on cone production and growth of young Douglas-fir,
western hemlock, and western red cedar on the U.B.C. Research
Forest. Univ. B.C. Fac. For. Bull. No. 5.
SNEDECOR, G. W. 1961. Statistical methods applied to experiments in
agriculture and biology. Iowa State University Press, Ames, IA.
TARRANT, R. F., L. A. ISAAC, and F. F. CHANDLER, JR. 1951.
Observations on litter fall and foliage nutrient content of some
Pacific Northwest tree species. 1. For. 49: 914-915.
VAN DEN DRIESSCHE, R. 1976. Mineral nutrition of western hemlock.
In Western Hemlock Management Conference Proceedings, Seattle,
WA, May 1976. Edited by W. A. Atkinson and R. J. Zasoski.
College of Forest Resources, University of Washington, Seattle,
WA. pp. 56-70.
.. .
VIRO, P. J. 1965. Estimation of the effect of forest fertilizatIOn.
Metsantutkimuslaitoksen Julk. (Commun. Inst. For. Fenn.) 59:
1-39.
WALKER, R. B., S. P. GESSEL, and P. G. HADDOCK. 1955. Greenhouse
studies in mineral requirements of conifers: western red cedar. For.
Sci. 1: 51-60.
WARREN, H. V., R. E. DELAVAULT, and R. J. IRISH. 1952.
Biogeochemical investigations in the Pacific Northwest. Geol. Soc.
Am. Bull. 63: 435-484.
ZOBEL, D. B. , and G. M. HAWK. 1980. The environment of
Chamaecyparis lawsoniana. Am. MidI. Nat. 103: 280-297.
.
About this file: This file was created by scanning the printed publication. Some mistakes introduced by scanning may remain.