Stereo photo series for quantifying forest residues in the Douglas-Fir-Hemlock type of the Willamette National Forest.

Abstract Feeding damage by black bears (Ursus americanus) to urea-fertilized 25-yr-old Douglas-firs (Pseudotsuga menziesii) in the Mount Hood National Forest, Oregon, resulted in tree mortality four times as severe as among unfertilized trees. Damage was most apparent following application of urea at 448 kg N/ha in 1972, and 224 kg N/ha in 1977. Only Douglas-fir, the dominant species in the stand, was attacked. Attacked trees were somewhat larger than the stand average, but the difference was not significant. Bears appeared to be attracted to the more vigorous trees, which were on fertilized plots. West. J. Appl. For. 4(1):13-15, January 1989.

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Conversion of SPORL pretreated Douglas fir forest residues into microbial lipids with oleaginous yeasts

RSC Advances ◽

10.1039/c5ra24430g ◽

2016 ◽

Vol 6 (25) ◽

pp. 20695-20705 ◽

Cited By ~ 7

Author(s):

Bruce S. Dien ◽

J. Y. Zhu ◽

Patricia J. Slininger ◽

Cletus P. Kurtzman ◽

Bryan R. Moser ◽

...

Keyword(s):

Douglas Fir ◽

Microbial Lipids ◽

Forest Residues ◽

Oleaginous Yeasts

Sugars were extracted from Douglas fir residues using SPORL pretreatment and cellulases. The sugars were converted to lipids producing a titer of 13.4 g l−1 in 3 d using a 2-stage culture.

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CONSUMPTION OF VARIOUS DOUGLAS-FIR CONE STRUCTURES BY BARBARA COLFAXIANA (LEPIDOPTERA: OLETHREUTIDAE)

The Canadian Entomologist ◽

10.4039/ent1091293-9 ◽

1977 ◽

Vol 109 (9) ◽

pp. 1293-1294

Author(s):

T. Evan Nebeker

Keyword(s):

Energy Transfer ◽

Seed Production ◽

Energy Budget ◽

Forest Ecosystem ◽

Larval Stage ◽

Douglas Fir ◽

National Forest ◽

Larval Instars ◽

Production Area

During 1971 a study was conducted to determine the amount of the various Douglasfir cone structures (bracts, scales, and seeds) consumed by the Douglas-fir cone moth, Barbara colfaxiana (Kft.), in the Buckhead Seed Production Area, Willamette National Forest, Oregon. It was not the intent of this study to develop a complete energy budget for B. colfaxiana, but rather to determine the number of calories consumed, on the average, by an individual during the larval stage. The behavior of the various larval instars has been discussed by Radcliffe (1952), Keen (1958), Hedlin (1960), and Nebeker (1977). The calorie was selected as the unit of measure due to its usefulness in modeling energy transfer from one component to another in the forest ecosystem.

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Do Shade and Shrubs Enhance Natural Regeneration of Douglas-Fir in South-Central Idaho?

Western Journal of Applied Forestry ◽

10.1093/wjaf/10.1.24 ◽

1995 ◽

Vol 10 (1) ◽

pp. 24-28 ◽

Cited By ~ 2

Author(s):

Michael Hunt Jones

Keyword(s):

Natural Regeneration ◽

Positive Association ◽

Soil Surface ◽

Douglas Fir ◽

National Forest ◽

Shrub Species ◽

Preparation Methods ◽

South Central ◽

Early Seedling ◽

Median Date

Abstract Shade duration and shrub composition in microsites with naturally regenerated Douglas-fir seedlings (Pseudotsuga menziesii var. glauca) were compared to randomly located control plots without seedlings in hot, dry group selection cuts in the southernmost Boise National Forest. Shade duration was estimated using a sighting device which allowed quantification of the degrees of the sun's arc intercepted by timber, shrubs, or other obstructions. Measurements were standardized for the median date for summer high temperatures. Seedlings received more whole-day (P<0.001) and afternoon (P<0.001) shade than control plots, and seedlings on southern exposures received more shade than those on other aspects. Seedling plots had more shrub cover than control plots (P<0.007). However, of nine shrub species examined, only buckbrush exhibited a significantly positive association with seedlings. Soil surface temperatures under buckbrush were reduced more than under other species, and unshaded surfaces remained above 50°C for extended time periods. These results suggest that natural regeneration of Douglas-fir may be enhanced by harvest practices and site preparation methods which provide shade during critical stages of germination and early seedling establishment. West. J. Appl. For. 10(1):24-28.

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A PARTIAL LIFE TABLE FOR THE DOUGLAS-FIR CONE MOTH, BARBARA COLFAXIANA (LEPIDOPTERA: OLETHREUTIDAE)

The Canadian Entomologist ◽

10.4039/ent109943-7 ◽

1977 ◽

Vol 109 (7) ◽

pp. 943-951 ◽

Cited By ~ 5

Author(s):

T. Evan Nebeker

Keyword(s):

Life Table ◽

Seed Production ◽

Critical Factor ◽

Douglas Fir ◽

National Forest ◽

Production Area ◽

Critical Age

AbstractA population of the Douglas-fir cone moth, Barbara colfaxiana (Kft.), was studied on the Buckhead Seed Production Area, Lowell Ranger District, Willamette National Forest, Oregon, during 1971. Factors contributing to the mortality of B. colfaxiana are presented in a partial life table and discussed. The egg – instar I was identified as the critical age interval and resinosis the critical factor.

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