Injection Treatments for Killing Bottom-Land Hardwoods

Abstract

Injection of undiluted dimethylamine salt of (2,4-dichlorophenoxy)acetic acid (2,4-D) containing 479 g/L killed several species of bottom-land hardwoods when applied in 1 or 2-ml dosages in injections spaced from edge-to-edge to 23 cm apart. Most hardwoods were easier to kill in June than in September or December. For greatest economy, treatments should be varied by species and seasons. A 4:1 mixture of triisopropanolamine salts of 2,4-D and 4-amino-3,5,6-trichloropicolinic acid (picloram) containing 305 g/L was effective on some species resistant to 2,4-D, including eastern persimmon (Diospyros virginiana L.), swamp privet (Forestiera acuminata (Michx.)Poir.), and bitter pecan (Carya x lecontei Little).