Availability of N and P in the forest floors of adjacent stands of western red cedar–western hemlock and western hemlock–amabilis fir on northern Vancouver Island

1993 ◽  
Vol 23 (4) ◽  
pp. 605-610 ◽  
Author(s):  
C. E. Prescott ◽  
M.A. McDonald ◽  
G.F. Weetman
Keyword(s):  
Forest Floor ◽  
Forest Type ◽  
Western Hemlock ◽  
Red Cedar ◽  
Floor Layer ◽  
Second Growth ◽  
Extractable P ◽  
Western Red Cedar ◽  
Forest Floors ◽  
Floor Material

Availability of N and P was compared in the forest floors of old-growth forests of western red cedar (Thujaplicata Donn)and western hemlock (Tsugaheterophylla (Raf.) Sarg.) (CH forests), and second-growth forests of western hemlock and amabilis fir (Abiesamabilis (Dougl.) Forbes) (HA forests) of windthrow origin. Five samples of each forest floor layer (litter, fermentation (woody and nonwoody), and humus (woody and nonwoody)) were collected from three forests of each type (CH and HA). All layers of CH forest floors had smaller concentrations of total and extractable N and mineralized less N during 40-day aerobic incubations in the laboratory. Total and extractable P was lower in the litter layer of CH forest floors. Seedlings of western red cedar, Sitka spruce (Piceasitchensis (Bong.) Carr.), western hemlock, and amabilis fir grown from seed in forest floor material from CH forests grew more slowly and took up less N and P than did seedlings grown in HA forest floor material. The low supply of N and P in CH forest floors may contribute to the nutrient supply problems encountered by regenerating trees on cutovers of this forest type.

Mass and nutrient content of woody debris and forest floor in western red cedar and western hemlock forests on northern Vancouver Island

1993 ◽  
Vol 23 (6) ◽  
pp. 1052-1059 ◽  
Author(s):  
Rodney J. Keenan ◽  
Cindy E. Prescott ◽  
J.P. Hamish Kimmins
Keyword(s):  
Forest Floor ◽  
Forest Type ◽  
Woody Debris ◽  
Nutrient Content ◽  
Vancouver Island ◽  
Western Hemlock ◽  
N Availability ◽  
Red Cedar ◽  
The Mean ◽  
Western Red Cedar

Biomass and C, N, P, and K contents of woody debris and the forest floor were surveyed in adjacent stands of old-growth western red cedar (Thujaplicata Donn)–western hemlock (Tsugaheterophylla (Raf.) Sarg.) (CH type), and 85-year-old, windstorm-derived, second-growth western hemlock–amabilis fir (Abiesamabilis (Dougl.) Forbes) (HA type) at three sites on northern Vancouver Island. Carbon concentrations were relatively constant across all detrital categories (mean = 556.8 mg/g); concentrations of N and P generally increased, and K generally decreased, with increasing degree of decomposition. The mean mass of woody debris was 363 Mg/ha in the CH and 226 Mg/ha in the HA type. The mean forest floor mass was 280 Mg/ha in the CH and 211 Mg/ha in the HA stands. Approximately 60% of the forest floor mass in each forest type was decaying wood. Dead woody material above and within the forest floor represented a significant store of biomass and nutrients in both forest types, containing 82% of the aboveground detrital biomass, 51–59% of the N, and 58–61% of the detrital P. Forest floors in the CH and HA types contained similar total quantities of N, suggesting that the lower N availability in CH forests is not caused by greater immobilization in detritus. The large accumulation of forest floor and woody debris in this region is attributed to slow decomposition in the cool, wet climate, high rates of detrital input following windstorms, and the large size and decay resistance of western red cedar boles.

Nitrogen mineralization and decomposition in forest floors in adjacent plantations of western red cedar, western hemlock, and Douglas-fir

1994 ◽  
Vol 24 (12) ◽  
pp. 2424-2431 ◽  
Author(s):  
C.E. Prescott ◽  
C.M. Preston
Keyword(s):  
Mass Loss ◽  
N Mineralization ◽  
Forest Floor ◽  
Douglas Fir ◽  
Western Hemlock ◽  
N Availability ◽  
Net N Mineralization ◽  
Red Cedar ◽  
Western Red Cedar ◽  
Forest Floors

To determine if western red cedar (Thujaplicata Donn) litter contributes to low N availability in cedar–hemlock forests, we measured concentrations of N and rates of net N mineralization in forest floors from single-species plantations of cedar, western hemlock (Tsugaheterophylla (Raf.) Sarg.), and Douglas-fir (Pseudotsugamenziesii (Mirb.) Franco) on the same site in coastal British Columbia. Concentrations of total and extractable N and rates of net N mineralization during laboratory incubations were lowest in the cedar forest floor and highest in Douglas-fir. Less C was mineralized in the cedar forest floor during incubation, and the amount of N mineralized per unit C was least in cedar. Rates of mass loss of foliar litter of the three species were similar during the first 50 weeks of a 70-week laboratory incubation, but cedar lost mass more quickly during the final 20 weeks. Rates of net N mineralization in the forest floors were significantly correlated with the initial percent N, C/N, % Klason lignin, and lignin/N of foliar litter. Foliar litter of cedar had lower concentrations of N and greater proportions of alkyl C (based on 13C NMR spectroscopy) than Douglas-fir litter. These characteristics of cedar litter may contribute to low N availability in cedar–hemlock forest floors. Concentrations of alkyl C (waxes and cutin) may be better than lignin for predicting rates of mass loss and N mineralization from litter.

Litter production and nutrient resorption in western red cedar and western hemlock forests on northern Vancouver Island, British Columbia

1995 ◽  
Vol 25 (11) ◽  
pp. 1850-1857 ◽  
Author(s):  
Rodney J. Keenan ◽  
Cindy E. Prescott ◽  
J.P. (Hamish) Kimmins
Keyword(s):  
Nutrient Availability ◽  
Forest Floor ◽  
Forest Type ◽  
Vancouver Island ◽  
The Other ◽  
Western Hemlock ◽  
Litter Fall ◽  
Red Cedar ◽  
N Concentration ◽  
Nutrient Use

Fine litter fall and concentrations of N and P in green foliage and foliar litter were measured in three species over 1 year in two forest types at three sites on northern Vancouver Island to explore the hypothesis that differences in nutrient use and cycling between the dominant tree species on each forest type contribute to differences in forest floor nutrient availability. Total annual aboveground fine litter fall was significantly higher in second-growth, windstorm-derived 85-year-old stands of western hemlock (Tsugaheterophylla (Raf.) Sarg.) and amabilis fir (Abiesamabilis (Dougl.) Forbes) forests (4137 kg•ha−1) than in adjacent old-growth forests of western red cedar (Thujaplicata Donn) and western hemlock (3094 kg•ha−1) occurring on similar sites. Cedar had significantly lower N concentration in green foliage (9.3 mg•g−1) and litter (4.3 mg•g−1) than the other species in each forest type. Hemlock had a higher litter N concentration in the hemlock–amabilis fir type (8.3 mg•g−1) than in the cedar–hemlock type (6.4 mg•g−1). Cedar resorbed a significantly higher percentage of N during leaf senescence (76%), than hemlock in the cedar–hemlock type (64%), hemlock in the hemlock–amabilis fir type (51%), or amabilis fir (18%). Nitrogen-use efficiency (litter-fall mass/litter N) was considerably higher in cedar (235 kg litter/kg N) than in the other species in either forest type (90–156 kg litter/kg N). These results suggest that differences within and between species in the two types in nutrient use and the amount of nutrients cycling through the litter fall and internal redistribution pathways are contributing to lower rates of nutrient cycling and forest floor nutrient availability in the cedar–hemlock type.

Feeding damage by bears in managed forests of western hemlock–western red cedar in midcoastal British Columbia

1993 ◽  
Vol 23 (1) ◽  
pp. 49-54 ◽  
Author(s):  
Thomas P. Sullivan
Keyword(s):  
British Columbia ◽  
Black Bears ◽  
Western Hemlock ◽  
Grizzly Bears ◽  
Feeding Damage ◽  
Managed Forests ◽  
Red Cedar ◽  
Total Percentage ◽  
Second Growth ◽  
Western Red Cedar

This study measured the incidence of feeding damage in 1989 and 1990 by black bears (Ursusamericanus Pallas), and possibly by grizzly bears (Ursusarctos L.), within managed and unmanaged second-growth western hemlock (Tsugaheterophylla (Raf.) Sarg.)–western red cedar (Thujaplicata Donn) forest stands near Jennis Bay, 39 km northwest of Port Hardy, British Columbia. Tree mensuration (1989) and damage assessments (1989 and 1990) were conducted in 69 sample plots located in stands that were spaced in 1980 to 1982, when the trees were juvenile, and in 19 plots located in a nearby unspaced (control) stand. Western red cedar, which represented 13.6% of the managed stands, was the most severely damaged species (cumulative attack of 63.8% in 1989, increasing to 69.1% in 1990). Western hemlock, the major tree species, had <0.5% of trees attacked, and amabilis fir (Abiesamabilis (Dougl.) Forbes) was not attacked. Cumulative incidence of damage to red cedar in the control stand was 66.7% in 1989, increasing to 71.4% in 1990. The annual incidence of attack in 1990 was 18.1% in the spaced stands and 16.7% in the control stand. The total percentage of girdled cedar stems (mortality) was 10.7% in the control and 23.3% in the spaced stands overall. Bear damage clearly declined during 1990, which may be related to dispersal or removal (hunting) of animals from the general area or to a declining number of cedar trees (30%) that remain unattacked by bears. Crop tree selection against red cedar in future spacing projects could alleviate bear attacks.

Mass Transfer Characteristics of Western Hemlock and Western Red Cedar

Holzforschung ◽  
2002 ◽  
Vol 56 (2) ◽  
pp. 185-190 ◽  
Author(s):  
Anastasios Koumoutsakos ◽  
Stavros Avramidis
Keyword(s):  
Mass Transfer ◽  
Western Hemlock ◽  
Transfer Characteristics ◽  
Red Cedar ◽  
Western Red Cedar

Equations for Estimating Browse Biomass of Red Huckleberry, Western Red-Cedar, and Deer Fern by Vertical Profile

1992 ◽  
Vol 7 (2) ◽  
pp. 48-50 ◽  
Author(s):  
Nicholas J. Smith ◽  
Alan McLeod
Keyword(s):  
Odocoileus Hemionus ◽  
Thuja Plicata ◽  
Regression Equations ◽  
Odocoileus Hemionus Columbianus ◽  
Height Profile ◽  
Winter Range ◽  
Red Cedar ◽  
Blechnum Spicant ◽  
Second Growth ◽  
Western Red Cedar

Abstract Edible biomass estimating regression equations were developed for red huckleberry (Vaccinium parvifolium), understory western red-cedar (Thuja plicata) and deer fern (Blechnum spicant) growing in potential second-growth Columbian black-tailed deer (Odocoileus hemionus columbianus) winter range on Vancouver Island, B.C. Vertical edible biomass height profile equations were also developed for red huckleberry and western red-cedar. These models may be used to objectively and conveniently help assess the amount of forage available to deer during severe winters. West. J. Appl. For. 7(2):48-50.

Responses of western hemlock, Pacific silver fir, and western red cedar plantations on northern Vancouver Island to applications of sewage sludge and inorganic fertilizer

1993 ◽  
Vol 23 (9) ◽  
pp. 1815-1820 ◽  
Author(s):  
G.F. Weetman ◽  
M.A. McDonald ◽  
C.E. Prescott ◽  
J.P. Kimmins
Keyword(s):  
Sewage Sludge ◽  
Vancouver Island ◽  
Western Hemlock ◽  
Municipal Sewage ◽  
Municipal Sewage Sludge ◽  
Phosphorus Fertilization ◽  
Silver Fir ◽  
Nitrogen And Phosphorus ◽  
Red Cedar ◽  
Western Red Cedar

A field experiment was designed to determine whether or not municipal sewage sludge would be effective for fertilization for chlorotic and checked plantations of western hemlock (Tsugaheterophylla (Raf.) Sarg.), Pacific silver fir (Abiesamabilis (Dougl.) Forbes), and western red cedar (Thujaplicata Donn ex. D. Don) already shown to be responsive to conventional nitrogen and phosphorus fertilization. Sewage sludge was applied at an estimated rate of 500 kg N/ha and 133 kg P/ha and ammonium nitrate and triple superphosphate were applied at 225 kg N/ha and 75 kg P/ha to plots planted 8 years earlier on a cutover of old-growth cedar–hemlock forest. Current-year leader growth and foliar vector analyses showed that the trees responded to both treatments during the first growing season with a doubling or tripling of growth rates and improved nutrition. The apparent problem of insufficient sulphur following nitrogen and phosphorus fertilization was not seen in trees treated with sludge. There were no apparent problems in micronutrient supply in these plantations. The extensive area of checked plantations on northern Vancouver Island present an opportunity for the disposal of sewage sludge.

Root systems of older immature hemlock, cedar, and Douglas-fir

1987 ◽  
Vol 17 (11) ◽  
pp. 1348-1354 ◽  
Author(s):  
S. Eis
Keyword(s):  
Root Systems ◽  
Douglas Fir ◽  
Western Hemlock ◽  
Organic Horizon ◽  
Red Cedar ◽  
Western Red Cedar ◽  
Absorbing Roots

Root systems of eight western hemlock (Tsugaheterophylla (Raf.) Sarg.), eight western red cedar (Thujaplicata Donn.), and six Douglas-fir (Pseudotsugamenziesii (Mirb.) Franco) trees, average age about 50 years, average dbh 26.3 cm, were hydraulically excavated. The sizes and shapes of the root systems are given and the root systems and roots are described. Fresh and dry weights of roots of all vegetation averaged 36 and 14 t/ha and were similar for all three species. Fine absorbing roots were distributed mainly in the organic horizon and immediately below it, i.e., in the top 10 or 15 cm of the soil; their turnover appears rapid. Their ovendry weight averaged 210 g/m2 and their length averaged 4 km/m2.

Sign in / Sign up

Export Citation Format

Share Document