Control Method and Time of Emergence Effects on Florida Beggarweed (Desmodium tortuosum) Competition in Peanut (Arachis hypogaea)

Abstract Field experiments were conducted to evaluate control method and time of emergence effects on Florida beggarweed competition in peanut. Two day old cotyledon stage Florida beggarweed were transplanted on the day of peanut emergence or 21 days after peanut emergence (DAPE). Treatments were a weed-free check, Florida beggarweed check established at peanut emergence, chlorimuron applied postemergence (POST) 49 or 63 DAPE, Florida beggarweed clipped weekly to the crop canopy after reaching 15 cm in height, Florida beggarweed clipped beginning at 63 DAPE, mowing of Florida beggarweed at 63 DAPE, and paraquat 63 DAPE. In other treatments paraquat was applied 21 DAPE early postemergence (EPOST), or paraquat was applied EPOST followed by chlorimuron 63 DAPE to a Florida beggarweed infested or weed-free treatment. Prior to treatment application, 98% of Florida beggarweed transplanted at peanut emergence survived. When chlorimuron was applied at 63 DAPE, 93% of Florida beggarweed established at peanut emerg...