Production of native grasses following aerial application of 1.12 kg/ha of 2.4.5-T ((2,4,5-trichlorophenoxy)acetic acid), 2,4,5-T + dicamba (3,6-dichloro-o-anisic acid), or 2,4,5-T + picloram (4-amino-3,5,6-trichloropicolinic acid) (1:) to a south Texas mixed-brush (Prosopis-Acacia) community was significantly increased by all herbicide treatments the year of application, by the herbicide combinations during the second year, but only by 2,4,5-T + picloram the third year after treatment. Moisture-use efficiency based on kg/ha native grass produced/cm precipitation was greastest where the herbicide combinations were applied. Defoliation of woody plants in years of above-average rainfall resulted in favorable grass production responses regardless of herbicide(s). However, range improvement over the 3-yr of study was dependent on maintenance of herbicide effectiveness, especially control of underbrush which resulted only where 2,4,5-T + picloram were applied. Consumption of native grass was a direct function of availability in response to brush control as augmented by rainfall. Forb production was reduced by all herbicides the year of treatment and by 2,4,5-T + picloram the year following application, but was not reduced by any treatment during the third growing season.

Double chainingfollowed by raking and stacking hea* stands of south Texas mixed brush was more effective than double chaining alone or chaining one way, based on compararive degree 01 brush control, range forage production, and fomge consumption by livestock. In a brush stand composed primarily of honey mesquite, spiny hackberry, and lime pricklyash, double chaining followed by raking and stacking reduced woody plant densities by 88%. increased oven-dq forage production by owr 1,600 kg/ha, and increased forage consumption by 950 kg/ha 0s compared to untreated areas a year after freafmenf. Double chaining alone was less effective rhan double chaining, raking, andstacking inpromoringforageproducfion and consumprion and did nor improve management eflciency. Chaining one way was not considered an effective practice.