Early Postemergence Herbicide Weed Control in Onions

Onions treated with bromoxynil (Buctril7) or oxyfluorfen (Goal7) at the time when the first true leaf was emerging were not injured. No significant onion crop stand reduction occurred from any of the postemergence (POST) treatments. Onion height was not affected by any of the POST treatments through the season. A single application of Goal or Buctril offered up to 7 WAT of very good weed control with excellent crop safety. Onions treated at the typical 2-leaf stage of growth with Buctril or Goal exhibited no significant crop injury. Delayed and reduced control of knotweed (Polygonum aviculare) could have contributed to the decreased onion yield in the herbicide treated onions compared to the handweeded check. Onions in the untreated check were significantly reduced compared to Goal treated onions or the handweeded check