Effects of Simulated Browsing on Spiny Hackberry after Top Removal

Abstract

Spiny hackberry (Celtis paIlida) regrows readily after top removal. Our objective was to determine effects of various simulated browsing intensities in fall and early winter on regrowth and nntritional qnality of spiny hackberry af-ter top removal. Spiny hackberry plants were cut to a l0 inch stump height in June 1984 and regrowth was removed either once (6 months after top removal) or twice (3 and 6 months after top removal) at intensities of 0, 25, 50, 75, and 1000/0. Standing crop and number of sprouts per shrub were measured 13 months after top cutting to determine recovery. Crude protein (CP), neutral detergent fiber (NDF), in vitro organic matter digestibility (IVOMD), calcium (Ca), potassium (K), and phosphorous (P) content of regrowth subjected to 0 and 1000/0defoliation (3 and 6 months after top removal) was determined at 3, 6, and 13 months after top cutting. Defoliation at the intensities and frequencies tested had no significant (P > 0.05) effect on standing crop or number of sprouts per plant. Crude protein content, P content, NDF, and IVOMD of regrowth exceeded that of controls (not snbjected to top removal) at 3 and 13 months after top removal. Calcium content was lower in regrowth than in controls 3 and 6 months after treatment. Regrowth and controls had similar K levels. Fall and early winter browsing of plants subjected to sum-mer top removal may have little effect on nutritional quality and vigor of regrowth the following growing season.