Determination of Dihydroquercetin in Douglas Fir and Western Larch Wood

G. M. Barton; J. A. F. Gardner

doi:10.1021/ac60134a033

Root Growth Potential and Microsite Effects on Conifer Seedling Establishment in Northern Idaho

Forests ◽

10.3390/f12050597 ◽

2021 ◽

Vol 12 (5) ◽

pp. 597

Author(s):

Jacob A. Reely ◽

Andrew S. Nelson

Keyword(s):

Root Growth ◽

Douglas Fir ◽

Seedling Quality ◽

Growth Potential ◽

Larix Occidentalis ◽

Root Growth Potential ◽

Western Larch ◽

Neighborhood Conditions ◽

Seedling Performance ◽

Survival And Growth

Environmental conditions and seedling quality interact to produce complex patterns of seedling survival and growth. Root growth potential (RGP) is one metric of seedling quality that can be rapidly measured prior to planting, but the correlation of RGP and seedling performance is not consistent across studies. Site factors including microsite objects that cast shade and competing vegetation can also influence seedling performance. We examined the effects of RGP, presence/absence of a microsite object, and competition cover on the survival and growth of three native conifers to the Inland Northwest, USA, over 5 years. We found that RGP had no effect on the survival or growth of western larch (Larix occidentalis), Douglas fir (Pseudotsuga menziesii var. glauca), and grand fir (Abies grandis) at a mesic north aspect site and a xeric south aspect site. Comparatively, the presence of a microsite increased the odds of survival by 37% for western larch and 158% for grand fir, while the absence of forb cover increased the odds of survival of western larch by 72% and of grand fir by 26%. Douglas fir was less sensitive to microsites and competition. The strong effects of neighborhood conditions around seedlings help inform silvicultural practices to enhance the establishment of western larch and grand fir, including planting seedlings near shading objects and competition control, while these practices may not be as important for Douglas fir.

Download Full-text

Determination of the Year-To-Year Variation in Growing Season Water Use of a Douglas-Fir Stand

The Forest-Atmosphere Interaction ◽

10.1007/978-94-009-5305-5_15 ◽

1985 ◽

pp. 235-254 ◽

Cited By ~ 8

Author(s):

D. L. Spittlehouse

Keyword(s):

Water Use ◽

Growing Season ◽

Douglas Fir

Download Full-text

Determination of the natural durability of larch wood (Larix decidua Mill.) from the Western Italian Alps

Holzforschung ◽

10.1515/hf.2004.123 ◽

2004 ◽

Vol 58 (6) ◽

pp. 678-681 ◽

Cited By ~ 11

Author(s):

Anna Gambetta ◽

Debora Susco ◽

Roberto Zanuttini

Keyword(s):

Larix Decidua ◽

Natural Durability ◽

Italian Alps ◽

Larch Wood

Download Full-text

Effects of variations in stand structure on development of mixed-species stands in eastern Washington

Canadian Journal of Forest Research ◽

10.1139/x93-072 ◽

1993 ◽

Vol 23 (3) ◽

pp. 545-552 ◽

Cited By ~ 12

Author(s):

David F. Cobb ◽

Kevin L. O'hara ◽

Chadwick D. Oliver

Keyword(s):

Stand Structure ◽

Lodgepole Pine ◽

Douglas Fir ◽

Cascade Range ◽

Stand Development ◽

Mixed Species ◽

Western Larch ◽

Development Patterns ◽

Large Numbers ◽

Eastern Washington

The development of six mixed-species, even-aged stands was reconstructed in the eastern Washington Cascade Range. All stands were within the Grand Fir Climax Series and began following stand replacement disturbances. Western larch (Larixoccidentalis Nutt.) and lodgepole pine (Pinuscontorta Dougl. ex Loud.), when present, formed an upper stratum over interior Douglas-fir (Pseudotsugamenziesii var. glauca (Beissn.) Franco) and grand fir (Abiesgrandis (Dougl.) Lindl.) in all six stands. Establishment patterns and species composition affected stand development patterns. Douglas-fir benefitted from the absence of lodgepole pine; grand fir benefitted from the absence of Douglas-fir, but apparently not from the absence of lodgepole pine. Lodgepole pine had faster initial diameter growth rates than western larch when it became established relatively early and in large numbers.

Download Full-text

Perpendicular-to-Grain Strength of Douglas-Fir

Canadian Journal of Civil Engineering ◽

10.1139/l75-005 ◽

1975 ◽

Vol 2 (1) ◽

pp. 50-57 ◽

Cited By ~ 16

Author(s):

J. D. Barrett ◽

R. O. Foschi ◽

S. P. Fox

Keyword(s):

Experimental Data ◽

Brittle Fracture ◽

Survival Probability ◽

Douglas Fir ◽

Curved Beams ◽

Allowable Stresses ◽

Laminated Material

Weibull's theory of brittle fracture is applied to the determination of strength of Douglas-fir wood in tension perpendicular to the grain. Results from tests on blocks of glued-laminated material uniformly stressed in tension are used to derive ultimate stresses, at a given survival probability, for pitched-tapered beams, curved beams, and griplam nail connections. The results of the theory are shown to be in agreement with experimental data. Allowable stresses are derived for blocks, pitched-tapered beams, curved beams, and the particular nailed connection studied.

Download Full-text