Conifer bole utilization by wood-boring beetles in western Oregon

1989 ◽  
Vol 19 (8) ◽  
pp. 943-947 ◽  
Author(s):  
H. Zhong ◽  
T. D. Schowalter
Keyword(s):  
Surface Area ◽  
Bark Beetles ◽  
Douglas Fir ◽  
Western Hemlock ◽  
Silver Fir ◽  
Conifer Species ◽  
Red Cedar ◽  
Colonization Density ◽  
Cerambycid Beetles ◽  
Wood Boring

We studied wood excavation by scolytid and cerambycid beetles in decomposing boles of four conifer species during the first two years on the ground in western Oregon. Colonization density and gallery volumes were measured in experimental boles (0.5 m diameter × 5 m length) of Douglas-fir (Pseudotsugamenziesii (Mirb.) Franco), western hemlock (Tsugaheterophylla (Raf.) Sarg.), Pacific silver fir (Abiesamabilis (Dougl.) Forbes), and western red cedar (Thujaplicata Donn). Ambrosia beetles (Coleoptera: Scolytidae) colonized boles only during the 1st year and were essentially restricted to Douglas-fir and western hemlock (removing 0.2% of the sapwood volume). Bark beetles (Coleoptera: Scolytidae) colonized boles only in the 1st year, primarily in Douglas-fir and Pacific silver fir (removing 7–8% of the phloem surface area). Wood borers (Coleoptera: Cerambycidae) excavated an additional 2.3% of the phloem surface area of Pacific silver fir in the 1st year and continued to excavate all species except Douglas-fir during the 2nd year. Consequences for the decomposition process are discussed.

Distribution and variation of extractable total phenols and tannins in the logs of four conifers after 1 year on the ground

1989 ◽  
Vol 19 (8) ◽  
pp. 1030-1036 ◽  
Author(s):  
Rick G. Kelsey ◽  
Mark E. Harmon
Keyword(s):  
Decay Resistance ◽  
Douglas Fir ◽  
Decay Rates ◽  
Western Hemlock ◽  
Silver Fir ◽  
Total Phenols ◽  
Outer Bark ◽  
Inner Bark ◽  
Red Cedar ◽  
Low Concentrations

Concentrations of extractable total phenols and tannins have been analyzed in the outer bark, inner bark, sapwood, and heart wood from logs of four conifer species, after 1 year on the ground. To estimate decay rates, initial tissue densities were compared with those after 1 and 2 years of decomposition. The four species studied, Pacific silver fir (Abiesamabilis Dougl. ex Forbs), western hemlock (Tsugaheterophylla (Raf.) Sarg.), Douglas-fir (Pseudotsugamenziesii (Mirb.) Franco), and western red cedar (Thujaplicata D. Don) represent a gradient of decay resistance. Within a species, outer bark contained the greatest quantities of extractable total phenols followed by inner bark, heart wood, and sapwood. Outer barks also had the highest extractable tannin concentrations. Woody tissues contained very low concentrations of tannin compared with the barks. Total phenol concentrations were highest in the heart wood of red cedar, the most resistant, and lowest in the heart wood of silver fir, the least resistant. There was no obvious relationship between tannins, in any tissues, and the resistance gradient. Density measurements indicated minimal decay in all tissues after 1 year. At 2 years, the inner barks of Douglas-fir, western hemlock, and silver fir had decreased significantly. In general, tissues with the highest extractable phenols appear to be decomposing most slowly.

Tree population dynamics, growth, and mortality in old-growth forests in the western Olympic Mountains, Washington

1993 ◽  
Vol 23 (3) ◽  
pp. 512-519 ◽  
Author(s):  
Robert L. Edmonds ◽  
Ted B. Thomas ◽  
Kathleen P. Maybury
Keyword(s):  
Population Dynamics ◽  
Mortality Rate ◽  
Basal Area ◽  
Douglas Fir ◽  
Western Hemlock ◽  
Silver Fir ◽  
Red Cedar ◽  
Creek Watershed ◽  
Tree Population ◽  
Western Red Cedar

Tree population dynamics, growth, and mortality were determined in old-growth forested watersheds in the Hoh River valley, Olympic Peninsula, Washington: West Twin Creek (elevation 180–850 m) and Hoh Lake (elevation 1250–1525 m). Principal tree species at West Twin Creek are Douglas-fir (Pseudotsugamenziesii (Mirb.) Franco), western hemlock (Tsugaheterophylla (Raf.) Sarg.), Pacific silver fir (Abiesamabilis (Dougl.) Forb.), western red cedar (Thujaplicata D. Don), and Sitka spruce (Piceasitchensis (Bong.) Carr.). At Hoh Lake they are Pacific silver fir, mountain hemlock (Tsugamertensiana (Bong.) Carr.), and Alaska cedar (Chamaecyparisnootkatensis (D. Don) Spach). In 1985 stem densities for trees >5 cm DBH averaged 476 and 489 ha−1 in the upper and lower West Twin Creek watershed, respectively, and 508 ha−1 at Hoh Lake watershed. Stem densities at both sites declined 3–5% from 1985 to 1990. Western hemlock and Pacific silver fir were the dominant species at West Twin Creek and Hoh Lake, respectively. From 1985 to 1990 the annual mortality rate was 0.8% at West Twin Creek and 0.9% at Hoh Lake. Pacific silver fir had the highest mortality rate. No Douglas-fir or western red cedar trees died. The primary causes of mortality were as follows: suppression–unknown, diseases, insects, and windthrow. In 1985 basal areas were 77, 87, and 94 m2•ha−1 in the lower and upper West Twin Creek watershed and Hoh Lake watershed, respectively. There was a 5% increase and a 1% decrease in basal area from 1985 to 1990 in the lower and upper West Twin Creek watershed, respectively, and a 4% decrease at Hoh Lake. Western red cedar, Douglas-fir, and western hemlock increased in basal area, while the other species declined.

ATTACK BY GNATHOTRICHUS SULCATUS (COLEOPTERA: SCOLYTIDAE) ON STUMPS AND FELLED TREES BAITED WITH SULCATOL AND ETHANOL

1977 ◽  
Vol 109 (5) ◽  
pp. 675-686 ◽  
Author(s):  
J. A. McLean ◽  
J. H. Borden
Keyword(s):  
Bark Beetles ◽  
Douglas Fir ◽  
Western Hemlock ◽  
Systemic Insecticide ◽  
Dendroctonus Pseudotsugae ◽  
University Of British Columbia ◽  
Steady Decrease ◽  
Population Aggregation ◽  
The University

AbstractEthanol and sulcatol (6-methyl-5-hepten-2-ol), primary attractant and population aggregation pheromone, respectively, for Gnathotrichus sulcatus, were deployed alone or in combination on stumps and felled trees in the University of British Columbia Research Forest, Maple Ridge, B.C. On 18 April 1974, four Douglas-fir trees were felled at each of three locations, and four western hemlock trees were felled at each of three other locations. Felled trees and their respective stumps were baited on 26 April. Attacks by G. sulcatus and bark beetles were recorded at weekly intervals until 25 October. G. sulcatus attacks increased rapidly, reaching a maximum in June and July, followed by a steady decrease to October. Attacks by Dendroctonus pseudotsugae, Pseudohylesinus nebulosus, and P. tsugae showed characteristic seasonal trends, but were not correlated to any of the treatments. Over half the G. sulcatus attacks were on stumps, in which attack densities reached 683.5/m2. The greatest numbers of attacks were on stumps and logs baited with sulcatol or sulcatol plus ethanol. There was a significant interaction between sulcatol and ethanol on Douglas-fir but not on western hemlock. Significantly more G. sulcatus attacked ethanol-baited western hemlock stumps and logs than unbaited controls. However, there was no difference between the level of attack on ethanol-baited Douglas-fir and the controls. The role of ethanol is hypothesized to be more of a boring stimulant than a major attractant. Stumps baited with sulcatol and then treated with ethanolic solutions of systemic insecticide could be used to trap and kill field populations, thus reducing numbers of G. sulcatus being transported to log-booming grounds, dryland sorting areas, and sawmills.

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.

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.

Patterns of log decay in old-growth Douglas-fir forests

1987 ◽  
Vol 17 (12) ◽  
pp. 1585-1595 ◽  
Author(s):  
Phillip Sollins ◽  
Steven P. Cline ◽  
Thomas Verhoeven ◽  
Donald Sachs ◽  
Gody Spycher
Keyword(s):  
C:N Ratio ◽  
Dry Weight ◽  
Douglas Fir ◽  
Time Span ◽  
Western Hemlock ◽  
Tissue Type ◽  
Old Growth ◽  
Total N ◽  
Red Cedar ◽  
Western Red Cedar

Fallen boles (logs) of Douglas-fir (Pseudotsugamenziesii (Mirb.) Franco), western hemlock (Tsugaheterophylla (Raf.) Sarg.), and western red cedar (Thujaplicata Donn) in old-growth stands of the Cascade Range of western Oregon and Washington were compared with regard to their physical structure, chemistry, and levels of microbial activity. Western hemlock and western red cedar logs disappeared faster than Douglas-fir logs, although decay rate constants based on density change alone were 0.010/year for Douglas-fir, 0.016/year for western hemlock, and 0.009/year for western red cedar. We were unable to locate hemlock or red cedar logs older than 100 years on the ground, but found Douglas-fir logs that had persisted up to nearly 200 years. Wood density decreased to about 0.15 g/cm3 after 60–80 years on the ground, depending on species, then remained nearly constant. Moisture content of logs increased during the first 80 years on the ground, then remained roughly constant at about 250% (dry-weight basis) in summer and at 350% in winter. After logs had lain on the ground for about 80 years, amounts of N, P, and Mg per unit volume exceeded the amount present initially. Amounts of Ca, K, and Na remained fairly constant throughout the 200-year time span that was studied (100-year time span for Na). N:P ratios converged toward 20, irrespective of tree species or wood tissue type. C:N ratios dropped to about 100 in the most decayed logs; net N was mineralized during anaerobic incubation of most samples with a C:N ratio below 250. The ratio of mineralized N to total N increased with advancing decay. Asymbiotic bacteria in fallen logs fixed about 1 kg N ha−1 year−1, a substantial amount relative to system N input from precipitation and dry deposition (2–3 kg ha−1 year−1).

Water stress and survival of three species of conifer seedlings planted on a high elevation south-facing clear-cut

1987 ◽  
Vol 17 (9) ◽  
pp. 1115-1123 ◽  
Author(s):  
N. J. Livingston ◽  
T. A. Black
Keyword(s):  
Survival Rates ◽  
High Elevation ◽  
Douglas Fir ◽  
Western Hemlock ◽  
Silver Fir ◽  
High Survival ◽  
High Survival Rate ◽  
Poor Survival ◽  
Tolerance Mechanisms ◽  
Clear Cut

Douglas-fir (Pseudotsugamenziesii (Mirb.) Franco), western hemlock (Tsugaheterophylla (Raf.) Sarg.), and Pacific silver fir (Abiesamabilis (Dougl.) Forbes) container-grown 1-0 seedlings were spring planted on a south-facing high elevation clear-cut located on Mount Arrowsmith, Vancouver Island, British Columbia. Treatments, which included inclining seedlings to the southwest, provision of shade cards, irrigation, and irrigation and shade cards combined, were applied to determine whether modification of seedling microclimate would increase survival. Highest survival rates, regardless of treatment, were shown by Douglas-fir. By April 1984, 72 and 82% of untreated Douglas-fir seedlings planted in 1981 and 1982, respectively, survived, whereas survival of treated seedlings ranged from 81 to 95%. The high survival rate in Douglas-fir appeared to be due to their high drought tolerance. The osmotic potential of unirrigated Douglas-fir seedlings declined by over 1.1 MPa during the course of the 1982 growing season in response to decreasing soil water potentials and consequently turgor was maintained in the foliage. Transpiration rates of these seedlings were never less than 50% of those that were irrigated. Western hemlock and Pacific silver fir seedlings exhibited very poor survival, possibly owing to the lack of stress avoidance and tolerance mechanisms. Survival rates of the two species were increased by shade cards and irrigation but never exceeded 64%.

Root Grafts and their Silvicultural Implications

1972 ◽  
Vol 2 (2) ◽  
pp. 111-120 ◽  
Author(s):  
S. Eis
Keyword(s):  
Root System ◽  
Vancouver Island ◽  
Douglas Fir ◽  
Western Hemlock ◽  
Slow Recovery ◽  
Red Cedar ◽  
Western Red Cedar ◽  
Root Grafts

Many trees in stands of Douglas fir, western hemlock and western red cedar on Vancouver Island were joined by functional grafts. In a partially cut stand, 45% of the stumps showed evidence of continued growth and half of these (23%) were still growing vigorously more than 22 years after logging. On experimentally detopped trees, growth extended several meters up the bole. Dominant trees usually supported the growth of the root system and lower boles of grafted suppressed trees.Translocation through grafts may partially explain the frequent stagnation and slow recovery of stands after thinning from above, and may be involved in the usually rapid increase of growth after thinning from below. It is probably a contributing factor in establishing dominance and determining mortality in overtopped trees. In species that graft freely, the use of silvicides in spacing and thinning treatments should be restricted to young stands before grafts are established.

Use of the ectomycorrhizal fungus Laccarialaccata in forestry. I. Consistency between isolates in effective colonization of containerized conifer seedlings

1982 ◽  
Vol 12 (3) ◽  
pp. 469-473 ◽  
Author(s):  
Randy Molina
Keyword(s):  
Seedling Growth ◽  
Ponderosa Pine ◽  
Dry Weight ◽  
Sitka Spruce ◽  
Ectomycorrhizal Fungus ◽  
Douglas Fir ◽  
Western Hemlock ◽  
Conifer Species ◽  
Colonization Success ◽  
Inoculation Treatment

Four isolates of the ectomycorrhizal fungus Laccarialaccata (Scop. ex Fr.) Berk and Br. were inoculated singly onto containerized Douglas-fir (Pseudotsugamenziesii (Mirb.) Franco), ponderosa pine (Pinusponderosa Dougl. ex Laws.), Sitka spruce (Piceasitchensis (Bong.) Carr.), and western hemlock (Tsugaheterophylla (Raf.) Sarg.) seedlings to detect ecotypic variation in colonization success and effects on seedling growth. All isolates formed well-developed ectomycorrhizae on all inoculated seedlings. Abundance ratings of short roots colonized did not differ between the four isolates for any conifer species; most inoculated seedlings developed ectomycorrhizae on over 80% of their short roots. There were also no differences between isolates in affecting seedling height, stem diameter, and dry weight of tops and roots for all conifer species. Inoculations did not improve seedling growth over uninoculated controls. Uninoculated controls of Douglas-fir and ponderosa pine had significantly greater dry weight than their inoculated seedlings; growth of Sitka spruce and western hemlock seedlings was not affected by any inoculation treatment. Laccarialaccata vigorously colonized the entire container rooting substrate and appears a prime candidate for artificial ectomycorrhizal inoculation of containerized western conifers.

Sign in / Sign up

Export Citation Format

Share Document