Considerations when Using Ethephon for Suppressing Dwarf and Leafy Mistletoe Infestations in Ornamental Landscapes    (View PDF)

David H. Adams, Susan J. Frankel, and John M. Lichter

Abstract: Ethephon [(2-chloroethyl) phosphonic acid] is registered for use in controlling dwarf and leafy mistletoe infestations in ornamental trees. Practical use of ethephon (as FlorelŪ at label rate) is limited to suppression of dwarf and leafy mistletoe spread. Ethephon at label rates causes abscission of aerial dwarf mistletoe shoots and partial abscission of leafy mistletoe shoots, but in either application the treated mistletoe plants are not killed. Resprouting of mistletoe infections will occur and retreatment will be needed to continue suppression of mistletoe fruiting. Whole tree spraying is not recommended due to the potential environmental and economic damage that may occur from spray drifting onto sensitive nontargets and excessive chemical use. Due to the lack of significant benefit of whole tree or direct cluster spraying of leafy mistletoe with ethephon at label rate, its use for this purpose is not recommended.

Keywords:

https://doi.org/10.48044/jauf.1993.055