|Fansler, Valerie - OREGON STATE UNIVERSITY|
|Borman, Michael - OREGON STATE UNIVERSITY|
|Pyke, David - USGS,CORVALLIS OR|
Submitted to: Society for Range Management Meeting Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: August 10, 2006
Publication Date: February 9, 2007
Citation: Fansler, V., Mangold, J.M., Borman, M., Pyke, D. 2007. Increasing native plant diversity in crested wheatgrass stands [abstract]. Society for Range Management Meeting. Paper No.138. Technical Abstract: Crested wheatgrass (Agropyron cristatum (L.) Gaertn.) is a nonindigenous perennial grass that was introduced to North America to improve the condition of degraded rangelands. It has proven to be a successful revegetation species due to its superior ease of establishment, strong competitive ability, and resistance to excessive grazing. However, crested wheatgrass is criticized for its ability to form monotypic stands that result in low plant diversity. Our objective was to determine the effect of crested wheatgrass control methodologies and revegetation on plant community diversity using a successional-based approach. We hypothesized that control methodologies and revegetation would decrease crested wheatgrass density and cover, increase the presence of native species, and increase cheatgrass and annual forb density and cover. In 2005, at one site in southeastern Oregon, we treated 25-acres of an established crested wheatgrass stand with two control methods at two intensities: partial mechanical control (once disked), full mechanical control (twice disked), partial herbicide control (1/4 recommended rate of glyphosate), full herbicide control (full recommended rate of glyphosate), and an undisturbed control. In October of 2005, we seeded one half of each plot with 10 native species, representing three different functional groups. In June of 2006, we sampled the density and cover of crested wheatgrass, cheatgrass, seeded species, and any weedy species phenologically competitive with the seeded species. Compared to the control, preliminary results suggest that crested wheatgrass density decreased while cheatgrass density increased with all treatments except the full control mechanical, seeded species densities were increased by all treatments, and the annual forb Alyssum alyssoides (L.) L. density was increased by all treatments. Procedures are being repeated at the same site in 2006-2007. We believe that by using a successional approach to management, land managers can direct plant community dynamics to increase diversity and meet resource agency goals.