Ten herbicides (atrazine, azafenidin, chlorsulfuron, clopyralid, hexazinone, imazapic, imazapyr, metsulfuron, pendimethalin, and sulfometuron) were evaluated for phytotoxicity in first-year seedlings of eight conifer species (Douglas-fir, grand fir, noble fir, redwood, Sitka spruce, western hemlock, western red cedar, and western white pine). Six of these herbicides (atrazine, clopyralid, hexazinone, imazapyr, metsulfuron,...
The influence of shading intensity on performance, chlorophyll fluorescence emissions, the slope of the fluorescence induction curve, chlorophyll contents, and stomatal conductance of four Pacific Northwest conifer species [ponderosa pine (Pinus ponderosa Laws.), Douglas-fir
(Pseudotsuga menziesii (Mirb.) Franco), western redcedar (Thujaplicata Donn.), and western hemlock (Tsuga heterophylla (Raf.) Sarg.)] was...
To understand the effect of human-induced stresses on forests, there is a need for a method to separate effects of imposed stress from effects of natural climate stress. I developed an approach to predict forest response to climate stress using as indicators stable carbon isotopes in tree foliage and growth-rings....
Approximately 3-4 month-old containerized Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) seedlings (seed zone 262 and 271) were subjected to 6 moisture stress treatments (65, 53, 41, 29, 17 and 7% soil water content by volume of dry soil) starting July 4 to September 22, 1991 at Forest Research Laboratory's greenhouse at...
An experiment was established in 1992 in the central Sierra Nevada Mountains of California to assess the effects of high levels of surface organic residues, severely compacted soil, and shrub competition on the development of mixed conifer plantations. This study was conducted in 1997 to determine if selected combinations of...
A Study conducted at The Island, Lake Billy Chinook, in Central Oregon, examined
differences in the pattern of soil properties between a sagebrush-grass and a juniper-sagebrush-grass community. Juniper invasion is linked with the desertification
process in which the sagebrush shrubs and perennial grasses decline. Patterns in soil
nutrients and other...
