Dodder Control in Alfalfa with Dinoseb and D(-) (3-chlorophenylcarbamoyloxy)-2N-isopropylpropionamide

Field studies indicated that D(-) (3-chlorophenylcarbamoyloxy)-2N-isopropylpropionamide (RP-11755) at 3 lb/A controlled dodder (Cuscutaspp.) in alfalfa (Medicago sativaL.) as well as or better than the standard treatment, isopropylm-chlorocarbanilate (chlorpropham) at 6 lb/A. Control from 2-sec-butyl-4,6-dinitrophenol (dinoseb) at 12 lb/A (amine or phenol form) sometimes was equal but never superior to that from chlorpropham. Greenhouse studies indicated that vapors toxic to dodder seedlings evolved from soil treated with dinoseb (amine or phenol form) but not from soil treated with RP-11755.