This report is one of a series issued in cooperation with the Army-Navy-Civil Committee on Aircraft Design Criteria under the supervision of the Aeronautical Board. Information reviewed and reaffirmed 1956.
Using existing data from untreated research plots, we developed equations
for predicting 5-yr diameter-growth rate (ΔD₅), 5-yr height-growth
rate (ΔH₅), and 5-yr mortality rate (PM₅) for Douglas-fir [Pseudotsuga
menziesii (Mirb.) Franco] in the coastal region of the Pacific Northwest.
These equations are revisions of the equations constructed in 1995–1997
for...
A method is described to determine the distribution of the bending stresses in a wood beam when some of these stresses exceed the proportional limit. This is used to calculate the position of the neutral axis and the bending strength of some Douglas-fir beams. The calculated values agreed with the...
Diameter growth of Douglas-fir (Pseudotsuqa menziesii (Mirb.) Franco) estimated from increment cores was compared with that obtained from repeated measurements of tree diameter on permanent plots located in two Douglas-fir study areas in the central Coast Range of Oregon. Growth was measured for a 6-year period (1979-
1985). Diameter growth...
A review is made of methods which assess the bias
and non-normality of parameter estimates and predictions
obtained with nonlinear regression. Particular emphasis
is placed upon curvature measures of nonlinearity,
related measures of parameter and prediction bias, and
the effects of reparameterizations. Alternate models of
individual tree height growth are...
A branch mortality dating technique and whorl
sampling strategy were implemented to model five-year
crown recession from data collected on temporary
plots. Twenty-eight Douglas-fir from two levels-of-growing-
stock studies in Oregon and Washington were
first dissected to validate the proposed dating
technique and assess alternative sampling strategies.
Branch mortalities in...
The objective of this study was to assess the effects of
forest management intensity on long-term productivity of Pacific
Northwest Douglas-fir forests. The components of management intensity
included rotation length, timber utilization standard (whole
tree or bole only), method of slash treatment (remove/burn or leave)
and fertilization practice (urea nitrogen...
Forest growth and yield models are critical to supporting decision making in forestry, but often lack considerations for wood properties. The feasibility of simulating wood properties in the context of a Douglas-fir individual tree growth and yield model was evaluated. This assessment explored the effect of predicted sapwood width, stem...