|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.), an alien annual grass, is an important plant species in the Northern Great Plains. Understanding the relationship between population dynamics of this and associated species is critical for management of infested ranges. We studied the effect of Japanese brome and clipping western wheatgrass [Pascopyrum smithii Rydb. (Love)] on herbage production in a western wheatgrass dominated northern mixed-prairie community. In study (1) either all plants were left intact in a circle with a 3'8" diameter or all Japanese brome seedlings were removed during spring and early summer. In early July, biomass of western wheatgrass, Japanese brome, and all other vegetation were sampled to ground level in a circle with a 1'9" diameter located in the center of each plot. In study (2) the same brome removal treatments were applied, and in addition western wheatgrass tillers within the 3'8" diameter plots were clipped to ground level on May 15, June 15, or July 15. When all forage was harvested, hand weeding Japanese brome seedlings from rangeland had 2 effects. Forage production of western wheatgrass was only increased 240 lbs/acre by late June. However, total forage production was reduced 500 lb/acre. The increase in production of western wheatgrass was apparently due to an increase in plant density rather than plant size. Clipping western wheatgrass tillers before July generally reduced forage production 205 to 312 lb/acre, increased tiller density and reduced weight per tiller of western wheatgrass accumulated during the three harvest regions.