Location: Soil and Water Conservation ResearchTitle: Plant Community Development in a Dryland CREP in Northeastern Oregon Author
Submitted to: Agricultural Experiment Station Publication
Publication Type: Experiment Station
Publication Acceptance Date: 4/28/2010
Publication Date: 5/28/2010
Citation: Williams, J.D., Hartman, H.M., Spencer, L.M., Loiland, J.O. 2010. Plant Community Development in a Dryland CREP in Northeastern Oregon. Agricultural Experiment Station Publication. 2010. http://cbarc.aes.oregonstate.edu/dryland-research-report-2010-0 Interpretive Summary:
Technical Abstract: Riparian areas in dryland crop regions of the Intermountain Pacific Northwest have largely been converted to cropland or pasture during the last 140 years. Some formerly cultivated floodplains have become difficult to farm; enrollment of these lands into conservation programs provides the opportunity to use them as wildlife habitat and as buffer areas near streams. Our objective was to evaluate vegetation development on an USDA Conservation Reserve Enhancement Program site planted in 1999 in northeastern Oregon. We established permanent line transects to quantify vegetation cover as a measure of plant community composition adjacent to three stream segments based on the degree of channel incision. We collected data in 2000-2001 and 2007-2008. Vegetation cover in 2000-2001 was 100%, dominated by tall wheatgrass. Living plant material cover decreased from 98% in 2000-2001 to 33% in 2007 and 68% in 2008; dead plant residue significantly increased and tall wheatgrass cover decreased. Native species were present in similar percentages from 2000 to 2008, there was a shift from target to nontarget species. The 1999 seeding can be judged a success, especially with respect to providing ground cover for soil conservation and the establishment of tall wheatgrass. The increased ratio of dead to living plant material suggests that more active management (i.e., fire, grazing, or mowing) of the tall wheatgrass stand is needed to maintain its productivity and/or a healthy mix of multiple species.