Influence of Organosilicone Surfactants and Spray Nozzle Types on the Fate and Efficacy of Clopyralid on Honey Mesquite (Prosopis glandulosa)

Abstract

Greenhouse and laboratory experiments were conducted to evaluate the influence of two organosilicone surfactants and spray nozzle types on the spray deposition, absorption, translocation, and efficacy of the monoethanolamine salt of clopyralid on honey mesquite. Sylgard 309 or Silwet L-77 added to the spray solution at 0.1, 025 and 0.5% by vol did not increase spray deposition, absorption, translocation, or phytotoxicity of clopyralid applied at 140 g ae ha-1on honey mesquite compared to no surfactant An air-assist spray nozzle at 9.4 L ha-1by vol resulted in greater initial clopyralid deposit on honey mesquite than hydraulic nozzles at 9.4 or 187 L ha-1by vol, but air-assist application did not increase phytotoxicity compared to hydraulic nozzles.