Factors Affecting Budbreak in Honey Mesquite in West Texas

Abstract

Budbreak in honey mesquite in west Texas rarely occurs prior to the last spring frost. We monitored many trees from 1970 to 1980 attempting to better correlate mesquite mortality from herbicides to growth stage. In doing so, we found clues to the probable conditions triggering budbreak. Budbreak was closely correlated to daily minimum winter temperatures but totally unrelated to winter maximum, mean, or soil temperatures. Our data showed that the higher the number of consecutive days with minimums below -1°C during January 15 to February 14, the earlier spring budbreak would occur. Once chilling requirements were met, date of budburst then became a function of relatively warmer daily minimum temperatures from February 15 to March 15. Being able to predict budbreak (from equations developed herein) as early as February 15 and/or March 15 should give ranchers and herbicide applicators 4 to 6 weeks lead time in planning mesquite control programs.