Allometric equations are useful tools for predicting tree biomass when direct measurements are impractical. Any factor affecting plant growth can be a significant variable in allometric equations. Density and species proportion are spatial variables that influence tree growth and should be considered when developing allometric equations. This consideration is especially...
When Douglas-fir and red alder grow in mixture, interactions between the two species can be competitive, facilitative, or a combination of both over time. A number of factors have recently led to increased interest in managing these two species together for commercial production, and ongoing investigations are yielding important information...
Stem growth, stem form development, and the dynamics of crown recession in young red alder (Alnus rubra Bong.) were studied by analyzing annual growth rings of stems and
knots, annual height increments, projected crown areas, and branch diameters. Forty-one
trees were sampled from three plantation spacing studies, representing ages 1...
Red alder (Alnus rubra Bong.) is a common associate and a potentially severe competitor of Douglas-fir (Pseudotsuga menziesii var. menziesii [Mirb.] Franco) in the Oregon Coast Range. However, because it fixes nitrogen and increases rates of soil nutrient cycling, red alder has the potential to benefit Douglas-fir. The objective of...
This study characterized the nature and dynamics of interference in mixed red alder
(Alnus rubra Bong.)/Douglas-fir (Pseudotsuga menziesii [Mirb.] Franco) stands in the Pacific Northwest, USA. Long-term spatial and tree measurements from the Cascade Head (CH) and H.J. Andrews (HJA) Experimental Forests in western Oregon and Delezene Creek (DC), Washington...
The role of disturbance in seed germination and first-year survival of red alder (Alnus rubra) was studied over two growing seasons at four sites representing a climatic gradient within the central Coast Range of Oregon. Disturbance affected red alder seed
germination and seedling establishment by altering the temperature and moisture...
This study was designed to help elucidate what differences, if any, exist within the species Alnus rubra Bong., grown naturally at various elevations and locations throughout the Pacific Northwest and coastal Alaska. Increasing importance of the species, including both economic and silviculture values, prompted the investigation into the early growth...
The biomass and the composition of 15 stands of red alder (Alnus rubra Bong.) on river bottom sites in western Oregon was measured during August and early September, 1969. These stands ranged in age from two to 64 years. Biomass was found to vary from 134 k/ha (kilograms per hectare)...
Red alder (Alnus rubra Bong.) is recognized as an important source of nitrogen to
ecosystems that it inhabits. I examined N dynamics within alder trees, alder leaf litter, and the soil beneath alder leaf litter. ¹⁵Nitrogen, a stable isotope of N, was used as a tracer to follow the movement...
Nodulated roots of young red alder trees and soil samples were collected from a 5 year old clearcut on Mary's Peak, Oregon. Frankia was isolated from root nodules, andactinomycetes from nodules, roots, and soil. A total of 229 pure culture actinomycete isolates were recovered: 131 colonies from root surfaces, 52...
