Chemical Defoliation of Young, Budded Pecan Trees1

Abstract

Abstract Applications of ethephon, ethephon plus KI, ethephon plus HI, ametryne and VCS-438 in Oct. promoted good to excellent leaf abscission on young, budded pecan trees (Carya illinoensis Koch). Combinations of ethephon and KI caused greater leaf abscission than either material alone. Complete defoliation of the trees in 4 weeks was obtained with ametryne in both 1970 and 1971. Only paraquat affected bud break and growth of young trees the next spring. Patterns of leaf abscission resulting from various chemical treatments support the concept that factors in addition to ethylene are involved in pecan defoliation.