NUTRITIONAL QUALITY OF BROWSE AFTER BRUSH MANAGEMENT ON CROSS TIMBERSRANGELAND

We evaluated seasonal changes in browse quality 5-6 years after experi mental manipulations to control unwanted woody vegetation using combin ations of herbicide and fire on cross timbers rangeland in central Okl ahoma. The study area consisted of two 32-ha replications of untreated controls and 4 brush treatments (tebuthiuron and triclopyr used singl y or in combination with periodic prescribed burning); herbicides were applied in 1983 and fires initiated in 1985. Nutritional quality of b lackberry (Rubus spp.), coralberry, (Symphoricarpos orbiculatus Moench ), rough-leaf dogwood (Cornus drummondii Meyer), elm (Ulmus spp.), gre enbrier (Smilax spp.), hackberry (Celtis spp.), and smooth sumac (Rhus glabra L.) were assessed by measuring crude protein, in vitro dry mat ter digestibility, neutral detergent fiber, acid detergent fiber, and moisture content. Crude protein concentrations of browse were 14% high er on herbicide-treated areas compared to untreated controls and 11% h igher on triclopyr treatments compared to tebuthiuron treatments. In v itro dry matter digestibility was 9% higher on herbicide-treated areas compared to untreated controls. Fiber constituents and moisture conte nt were not influenced by brush treatments. Prescribed burning combine d with herbicide applications did not improve the quality of browse. O ur results indicate that browse quality can be improved for white-tail ed deer by applications of tebuthiuron or triclopyr and improvements p ersist for up to 6 years post treatment.