FIRE EFFECTS ON 4 GROWTH-STAGES OF SMOOTH BROME (BROMUS-INTERMIS LEYSS.)

The invasion and persistence of smooth brome (Bromus inermis Leyss.) a re serious problems facing managers of warm-season pastures and prairi e remnants in the Midwest. Although difficult to control, smooth brome can be reduced when tiller growing points are removed by management a ctivities such as prescribed fire. This study, conducted from 1988 thr ough 1991 at Mead, Nebraska, measured changes in smooth brome tiller d ensity and biomass in seeded, mixed-grass stands following spring pres cription burns. Burning was timed to coincide with four smooth brome g rowth stages and included repeated burns in consecutive years. Burning at tiller emergence did not affect smooth brome tiller density or bio mass in years when precipitation was normal or below normal. However, with above normal precipitation, smooth brome biomass more than double d the year after a tiller-emergence burn. Burning during tiller elonga tion, heading, and flowering significantly reduced smooth brome tiller density and biomass. Repeated burns, at tiller elongation and later s tages, maintained low smooth brome tiller density and biomass. A singl e burn, however, allowed partial to full recovery of smooth brome dens ity and biomass by the following year. Implications of the study are p resented for management consideration.