|Karl, M - USFS|
Submitted to: Research Update for Fort Keogh Livestock and Range Research Laboratory
Publication Type: Other
Publication Acceptance Date: September 1, 1997
Publication Date: N/A
Technical Abstract: Japanese brome (Bromus japonicus Thunb.) has invaded many northern mixed prairie communities. Understanding how defoliation affects the life cycle of this species is critical for proper management of communities infested with this annual. Objective of this study was to determine the effect of no clipping vs. clipping to 75 or 150 mm weekly or every 2 weeks for 65 to 70 days in a greenhouse. Response of Japanese brome tiller density, maximum leaf height, and above- and below-ground biomass were measured. Greatest biomass was produced in 1991 when a large amount of culmless vegetative shoots were clipped compared to 1992 when culmless vegetative shoots differentiating to culmed reproductive shoots were clipped. Generally increasing intensity of clipping increased maximum leaf heights, but reduced tiller numbers, and herbage, root, and total biomass production in 1991; increased tiller numbers, but reduced maximum leaf height, cumulative aboveground biomass and total biomass in most categories in 1992. Increasing frequency of clipping did not generally affect total biomass production. Although production of inflorescences was reduced by increasing intensity of clipping, some were produced with the most severe treatment, suggesting plant control of Japanese brome would be difficult with defoliation.