Skip to main content
ARS Home » Research » Publications at this Location » Publication #241117
Title: Effects of prescribed fire and herbicide application on cattle grazing and herbage production from yellow bluestem pastures

Author
item Gunter, Stacey
item GILLEN, ROBERT - Kansas State University

Submitted to: Professional Animal Scientist
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 9/22/2010
Publication Date: 11/1/2010
Citation: Gunter, S.A., Gillen, R.L. 2010. Effects of prescribed fire and herbicide application on cattle grazing and herbage production from yellow bluestem pastures. Professional Animal Scientist. 26:638-646.

Interpretive Summary: Prescribed fire and herbicides are commonly used tools to manage introduced grasses in the Southern Plains, but their effects on livestock production are not well documented. Because animal performance is usually improved with prescribed fire on native grasslands, it is assumed that this same benefit is received with introduced warm-season grasses. The objectives of this experiment were to determine the effects of prescribed fire or herbicides on the production of grazing beef steers, density and production of forbs, and production and nutritive value of grass in Old World bluestem pastures. The experiment was conducted over 3 yr (1998 to 2000) at the Southern Plains Experimental Range in northwestern Oklahoma. The untreated pastures (Control) were not burned or sprayed; all pastures were annually fertilized with 50 lb of nitrogen/acre from urea applied on April 15. The prescribed fire treatment (Burned) occurred annually between 27 March and 10 April. The herbicide treatment (Herbicide) consisted of an annual application of 0.8 lb of 2,4 dichlorophenoxyacetic acid and 2.8 g of metsulfuron methyl active ingredient (a.i.)/acre. Compared with the Control, prescribed fire decreased forb densities only in May of 1998, and Herbicide did not decrease forb densities in any year. Herbage DM production of Old World bluestem in August was not affected by treatment, averaging 5,829 lb/acre in exclosures and 4,098 lb/acre outside exclosures where grazing occurred. Crude protein and IVOMD concentrations were greater in Burned pastures when herbage was collected early in the grazing season compared with Control and Herbicide treatments. Body weight after the 92-d grazing season, BW gain, and BW gain/acre did not differ among treatments. Forb control with prescribed fire or the herbicides used in this experiment did not improve performance of cattle grazing Old World bluestem pasture.

Technical Abstract: Prescribed fire and herbicides are commonly used tools to manage introduced grasses in the Southern Plains, but their effects on livestock production are not well documented. The objectives of this experiment were to determine the effects of prescribed fire or herbicides on the production of grazing beef steers, density and production of forbs, and production and nutritive value of grass in Old World bluestem (Bothriochloa ischaemum (L.) Keng var. ischaemum) pastures. The experiment was conducted over 3 yr (1998 to 2000) at the Southern Plains Experimental Range in northwestern Oklahoma. The untreated pastures (Control) were not burned or sprayed. The prescribed fire treatment (Burned) occurred annually between 27 March and 10 April. The herbicide treatment (Herbicide) consisted of an annual application of 0.9 kg of 2,4 dichlorophenoxyacetic acid and 2.8 g of metsulfuron methyl (a.i.)/ha. Compared with the Control, prescribed fire decreased (P < 0.01) forb densities only in May of 1998, and Herbicide did not decrease (P >/= to 0.08) forb densities in any year. Herbage DM production of Old World bluestem in August was not affected (P >/= to 0.10) by treatment, averaging 6,529 kg/ha in exclosures and 4,590 kg/ha outside exclosures where grazed. Crude protein and IVOMD concentrations were greater (P /= to 0.57; 355, 353, and 358 or 101, 99, and 104 kg/steer for Control, Burned, and Herbicide, respectively). Moreover, BW gain/ha averaged 205, 203, and 214 kg and did not differ (P = 0.61) among Control, Burned, and Herbicide treatments, respectively. Forb control with prescribed fire or the herbicides used in this experiment did not improve performance of cattle grazing Old World bluestem pasture.