Submitted to: Society for Range Management Meeting Proceedings
Publication Type: Abstract Only
Publication Acceptance Date: October 1, 2002
Publication Date: February 1, 2003
Citation: HAFERKAMP, M.R. ANNUAL BROME SEED GERMINATION IN THE NORTHERN GREAT PLAINS. SOCIETY FOR RANGE MANAGEMENT MEETING PROCEEDINGS. 2003. Abstract #95. Technical Abstract: Japanese brome (Bromus japonicus Thunb) and downy brome (B. tectorum L.), alien weedy cool-season annual grasses have invaded thousands of acres of the Northern Great Plains, Great Basin, California Annual Grasslands, and Palouse Prairie. A general discussion on environmental control of Japanese brome seed germination will be presented. Abundance of brome is dependent upon availability of seed, amount and distribution of rainfall, temperature, and availability of soil nitrogen. More than 10,000 annual brome seeds can be present in a square yard in the mixed-grass prairie of the Northern Great Plains. A large portion of ripe seeds will generally germinate over a wide range of temperatures that often occur in late summer and autumn, but soils usually need to be moist for 3 to 5 days for seeds to germinate. However, a percentage of seeds that do not germinate by late September can become dormant when water is taken up at or below 32 deg F. This dormant state can last through the next winter, spring, and summer. This characteristic aids annual brome's persistence on rangelands, because seedlings emerging in August and September in any year likely comes from two seed crops, the current and previous year.