Purple Nutsedge Management in Florida Strawberry with Herbicides and a Modified Florida 3-Way Fumigation Program

Abstract

The “Florida 3-way” consists of chloropicrin 35% + 1,3-dichloropropene 65% followed by minicoulter application of metam potassium. We evaluated the efficacy of a modified version of the Florida 3-way in which chloropicrin 35% + 1,3-dichloropropene 65% was used as primary bed fumigant and consisted of different drip tape application timings (at the time of bed formation and 2 weeks after bed formation) of metam potassium or the use of herbicides (sulfentrazone and s-ethyl dipropylthiocarbamate) as the supplemental application for the control of purple nutsedge (Cyperus rotundus) in strawberry (Fragaria ×ananassa) fields. Efficacy of modified Florida 3-way was not significantly different from standard Florida 3-way; however, supplemental herbicide such as s-ethyl dipropylthiocarbamate and sulfentrazone provided better purple nutsedge control than supplemental metam potassium application in one of two experimental growing seasons. Addition of metam potassium to the chloropicrin 35% + 1,3-dichloropropene 65% did not result in additional purple nutsedge control in Florida 3-way, which indicates the limitations of this approach.