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.

Impact of feeding damage by the porcupine on western hemlock – Sitka spruce forests of north-coastal British Columbia

1986 ◽  
Vol 16 (3) ◽  
pp. 642-647 ◽  
Author(s):  
Thomas P. Sullivan ◽  
William T. Jackson ◽  
James Pojar ◽  
Allen Banner
Keyword(s):  
British Columbia ◽  
Small Diameter ◽  
Sitka Spruce ◽  
Control Measures ◽  
Western Hemlock ◽  
Feeding Damage ◽  
Red Cedar ◽  
Total Percentage ◽  
Second Growth ◽  
Coastal British Columbia

This study measured the incidence of feeding damage by porcupines (Erethizondorsatum Allen) within the second-growth western hemlock (Tsugaheterophylla Raf. (Sarg.)) – Sitka spruce (Piceasitchensis (Bong.) Carr.) forest of Khutzeymateen Inlet, 45 km northeast of Prince Rupert, British Columbia. Tree mensuration and damage assessments were conducted in 69 sample plots located on four transects. Western hemlock, which composed 67% of sampled stands, was the most severely (52.7% of trees, of which 5.1% were newly attacked) damaged species followed by Sitka spruce with minor (7.8%) damage. The less frequent amabilis fir (Abiesamabilis (Dougl.) Forbes) and western red cedar Thujaplicata Donn.) were not attacked. The total percentage of girdled (mortality) hemlock stems was 30.9%. Hemlock trees with a dbh > 27.4 cm had 55.9% of stems girdled. Porcupines attacked and girdled a significantly greater proportion of large than small diameter hemlock trees. Stems smaller than 125.5 cm dbh had little (3.7%) damage. Significantly more damage wounds were recorded in the middle and upper thirds of hemlock stems than in the lower bole. Dominant and codominant hemlock were preferred by porcupines in their feeding attacks. In combination with porcupine control measures, these stands clearly require some form of silvicultural treatment, such as sanitation spacing, conducted initially as an operational trial on at least a 20-ha block.

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.

OBSERVATIONS ON FOLIAGE NUTRIENT CONTENT OF SEVERAL CONIFEROUS TREE SPECIES IN BRITISH COLUMBIA

1965 ◽  
Vol 41 (2) ◽  
pp. 222-236 ◽  
Author(s):  
J. D. Beaton ◽  
A. Moss ◽  
I. MacRae ◽  
J. W. Konkin ◽  
W. P. T. McGhee ◽  
...  
Keyword(s):  
British Columbia ◽  
Lodgepole Pine ◽  
Nutrient Content ◽  
Douglas Fir ◽  
Western Hemlock ◽  
Red Cedar ◽  
Engelmann Spruce ◽  
Calcium Magnesium ◽  
Western Red Cedar ◽  
Coniferous Tree Species

Concentration of nitrogen, phosphorus, potassium, calcium, magnesium and sulphur in needles of alpine fir, amabilis fir, western red cedar, Douglas fir, western hemlock, lodgepole pine, Engelmann spruce and Sitka spruce trees growing in a number of areas of British Columbia was determined.Concentration of N, P, K, Ca, Mg and S in current needles of three groups of alpine fir seedlings was 1.05-1.85, 0.18-0.26, 0.70-1.08, 0.29-.044, 0.07-0.11, and 0.12-0.16 per cent, respectively. The nutrient content in the same order was 0.99, 0.16, 1.20, 0.30, 0.08, and 0.12 per cent in a single group of amabilis fir samples.In the lone set of western red cedar samples the concentrations of N, P, K, Ca, Mg and S were in the order of 0.73, 0.13, 0.52, 1.16, 0.10 and 0.07 per cent.The percentage of the six nutrients in current Douglas fir needles from seven locations was 0.88-1.37, 0.12-0.22, 0.38-0.70, 0.16-0.44, 0.07-0.18, and 0.14-0.25 for N, P, K, Ca, Mg and S, respectively.The nutrient content of current needles of western hemlock from three sites was N = 0.86-1.17, P = 0.11-0.19, K = 0.28-0.57, Ca = 0.18-0.27, Mg = 0.08-0.12 and S = 0.10-0.15 per cent.Nitrogen, P, K, Ca, Mg and S concentration in current needles from three lots of lodgepole pine seedlings was 1.18-1.77, 0.15-0.18, 0.45-0.62, 0.16-0.26, 0.11-0.14 and 0.12-0.21 per cent, respectively. The corresponding values in needles from older trees were in the order 0.97-1.12, 0.09-0.12, 0.35-0.39, 0.15-0.16, 0.08-0.12 and 0.09-0.11.Per cent N, P, K, Ca, Mg and S in current needles of three groups of Engelmann spruce seedlings was in the order 1.26-1.72, 0.21-0.29, 0.71-0.80, 0.44-0.58, 0.13-0.15 and 0.13-0.19. Concentration of these nutrients in older trees was 0.92-1.08, 0.20, 0.70-0.88, 0.28-0.33, 0.11-0.12 and 0.12-0.14 per cent, respectively.

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.

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.

Palynology and paleoecology of postglacial sediments in an anoxic basin, Saanich Inlet, British Columbia

1983 ◽  
Vol 20 (5) ◽  
pp. 873-885 ◽  
Author(s):  
Linda E. Heusser
Keyword(s):  
British Columbia ◽  
Pinus Contorta ◽  
Tsuga Heterophylla ◽  
Douglas Fir ◽  
Western Hemlock ◽  
Thuja Plicata ◽  
Alnus Rubra ◽  
Red Cedar ◽  
Saanich Inlet ◽  
Anoxic Basin

Varved, black clayey silts deposited in the marine waters of Saanich Inlet yield unusually abundant and diverse pollen assemblages derived from the coastal Douglas-fir (Pseudotsuga) and western hemlock (Tsuga heterophylla) forests of southwestern British Columbia. The 12 000 year palynological record chronicles the development of vegetation since ice left Saanich Inlet: the succession of pine (Pinus contorta) and alder (Alnus rubra) woodlands by forests characterized by Douglas-fir and oak (Quercus) and later by western hemlock and red cedar (Thuja plicata). Rapid deposition of annual layers of pollen, charcoal, and other terrigenous particles provides detailed evidence of changes in land use during the past few hundred years: settlement, logging, farming, and urbanization. Vegetational and climatic changes inferred from pollen spectra in the marine sediments of Saanich Inlet compare favorably with changes inferred from correlative pollen assemblages previously described from adjacent parts of Vancouver Island and the Fraser River valley.

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.

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