A special apparatus was developed in which the soil moisture
levels of several soil cells could be maintained independently by
various osmotic solutions at a selected temperature. The effect of
four soil moisture suctions and four soil temperatures on the rates
of transpiration, photosynthesis and respiration of monterey pine
seedlings...
A sequence of soil profiles was sampled along a climate-vegetation transect on the dated Mazama pumice fall in central
Oregon. The <2 μ size fraction from each sample was characterized
with respect to the relative significance of amorphous and
crystalline components, and the individual minerals of the latter
group were...
Snowbrush (Ceanothus velutinus), red alder (Alnus rubra), and
bitterbrush (Purshia tridentata) are three important nitrogen- fixing
nonleguminous species. They commonly grow in association with
commercially important conifers in western United States and conceivably
could be utilized to add nitrogen to forest ecosystems. Nitrogen
15 gas was used to study nitrogen...