Published online by Cambridge University Press: 12 June 2017
Field studies were conducted in Saskatchewan to evaluate the effect of herbicides on annual canarygrass (Phalaris canariensis L.) and associated weeds. Bromoxynil (3,5-dibromo-4-hydroxybenzonitrile) at 0.35 kg ai/ha, tank mixes of bromoxynil at 0.28 kg/ha plus the ester of MCPA [(4-chloro-2-methylphenoxy)acetic acid] at 0.28 kg ae/ha, linuron [N′-(3,4-dichlorophenyl)-N-methoxy-N-methylurea] at 0.28 kg ai/ha plus MCPA amine at 0.56 kg/ha, or propanil [N-(3,4-dichlorophenyI)propanamide] at 1.0 kg ai/ha plus MCPA ester at 0.28 kg/ha resulted in annual canarygrass seed and dry matter yields equal to the unsprayed check and excellent wild mustard (Sinapis arvensis L. # SINAR) and cow cockle (Vaccaria pyramidata Medik. # VAAPY) control. Metribuzin [4-amino-6-(1,1-dimethylethyl)-3-(methylthio)-1,2,4-triazin-5(4H)-one] at 0.21 kg ai/ha plus MCPA amine at 0.56 kg/ha reduced the crop stand in 1 out of 5 yr and seed yield every year. Postemergence application of difenzoquat (1,2-dimethyl-3,5-dipheny1-1H-pyrazolium) at 0.84 kg ai/ha or flamprop [N-benzoyl-N-(3-chloro-4-fluorophenyl)-DL-alanine] at 0.53 kg ai/ha, or preplant-incorporated triallate [S-(2,3,3-trichloro-2-propenyl)bis(1-methylethyl)carbamothioate] at 1.40 kg ai/ha optimized wild oat (Avena fatua L. # AVEFA) control with seed yields. Diclofop {(±)-2-[4-(2,4-dichlorophenoxy)phenoxy)propanoic acid} at 0.70 kg ai/ha severely damaged annual canarygrass in all years. Triallate applied at 1.40 kg/ha preplant or preemergence incorporated marginally reduced the crop stand and seed yield compared to the untreated controls in tolerance tests.