Yellow starthistle (Centaurea solstitialis L.) is an introduced Asteraceae that has become established on 10 million acres in the Pacific Northwest and California. This weed functions as an annual or short-lived perennial and depends on seeds for reproduction. Strategies of control that reduce plant fitness or lower seed production or...
Cheatgrass (Bromus tectorum L.) is a widespread exotic weed in the Intermountain sagebrush steppe. An annual grass, it is highly prolific and very competitive with native perennial grass seedlings. A clipping experiment carried out at two cheatgrass-dominated sites (Lincoln Bench and Succor Creek) in eastern Oregon analyzed effects of defoliation...
The pine butterfly (Neophasia menapia C. Felder & R. Felder) (Lepidoptera: Pieridae) is a relatively host-specific defoliator of ponderosa pine (Pinus ponderosa Dougl. ex Laws). From 2008 to 2012, the Malheur National Forest was subject to an outbreak of pine butterfly in ponderosa pine, peaking at ~100,000 ha of forest...
The effect of defoliation intensity and season on Douglas-fir growth
were studied in three replications in the Siuslaw National Forest during
1988-1990. Four intensities of defoliation were applied once in either spring or
summer 1988. Stem diameter and canopy area were linearly inversely
proportional to the level of defoliation. Defoliation...
Published January 1966. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog
This study was initiated to make some preliminary
evaluations of the effects of red alder (Alnus rubra,
Bong.) leaf fall on stream water quality, particularly
water color. Laboratory tests were also conducted
to better understand the effects of leaf loading, duration
of leaf leaching, and type of leaching on
changes...
