04-22-24-WS - Laserfiche WebLink

Home Browse Search

GREATjU RIVERlRIPW GREENING Graminoids Smooth Brome (Bromus inermis) Description Smooth brome is a perennial cool season grass introduced to North American from Eurasia as a forage crop. It is able to persist through drought and occasional flooding. It grows from 2-4 feet tall with an upright habit. The %" wide leaf blades have a prominent W- or M-shaped constriction across the blade. In fall the persistent leaves brown and curl on the stems. The inflorescence is an open panicle with flowers occurring on 4-10 erect branches from a main axis. Flowering occurs in June and July. When the achenes ripen, the lateral branches of the seedhead relax from their upright posture and nod sideways. Smooth brome reproduces from seed as well as by rhizomes which spread laterally through the soil. Mechanical Smooth brome often occurs in native grassland habits intermixed with warm season grasses. Because smooth brome is a cool season grass, it may be best controlled in this situation with well-timed prescribed burns. Burns timed for late spring when smooth brome is beginning to green up, but before the native grasses are actively growing will knock back the cool season grasses, although the burn will not kill the rhizomes. This same timing is advantageous to warm season native grasses which are slower to green -up in the spring. Repeated mowing can be used to set back smooth brome. However, repeated mowing can have adverse effects on populations of native species as well. Mowing combined with herbicide is a more effective treatment method. Mowing can be used to facilitate herbicide treatment of smooth brome. Mow and then allow brome to regrow before applying herbicide. Chemical Non -selective systemic herbicides (glyphosate) or grass specific herbicides (fluazifop-p-butyl) can be used to control smooth brome, particularly where it grows in monotypic stands. Where smooth brome is mixed with native grasses and forbs, treatment is best in early spring or late fall when native species are more likely to be dormant and less susceptible to the herbicides. Fall treatments favor the translocation of the chemical to the roots resulting in better control. Mowing can be used to condition a stand of smooth brome for an herbicide treatment. Mowing removes dead standing vegetation and promotes a flush of new growth. Another strategy for control is to apply a dormant overspray in areas where smooth brome provides a more dense cover. A grass specific herbicide can be applied in late fall if treatment is carefully timed when cool season grasses are still actively growing, but warm season grasses are not. Long-term Management Monitoring and follow-up treatments will be needed to obtain full control. Smooth Brome April May June July Aug Sept Oct Nov Dec - Mar Burn Foliar Herbicide Mow Flowering