WILD CARROT (DAUCUS-CAROTA) CONTROL IN NO-TILLAGE CROPPING SYSTEMS

Wild carrot is becoming a serious weed problem in Michigan continuous no-tillage crop production. Greenhouse and field research was conducte d to identify effective management strategies for wild carrot control in no-tillage cropping systems. In the greenhouse, PRE applications of acetochlor plus dichlormid (5.8:1 w:w), cyanazine, linuron plus chlor imuron (18:1), and metribuzin plus chlorimuron (10:1) and POST applica tions of bentazon, CGA-152005, clopyralid, cyanazine, and MON 12000 pr ovided the greatest control of wild carrot seedlings. In the field, PR E and POST treatments containing chlorimuron consistently controlled o verwintered wild carrot greater than 74% at 30 d after the POST applic ation in no-tillage soybean. Atrazine, MON 12000, nicosulfuron, and pr imisulfuron applied POST consistently controlled overwintered wild car rot greater than 78% al 30 DAT in no-tillage corn. Glyphosate at 0.84 or 1.68 kg ae/ha applied in October to established wild carrot provide d greater than 74% control the following spring. Early preplant (EPP) applications of glyphosate at 0.84 kg/ha in no-tillage soybean gave 95 and 24% control of overwintered wild carrot in St. Clair and Lenawee Counties, MI, respectively, at 70 DAT. PRE applications of glyphosate at 0.84 kg/ha controlled overwintered wild carrot less than 69% at 58 DAT in no-tillage corn and soybean. Fall applications of 2,4-D ester a t 1.12 kg ae/ha provided 18 and 88% control of wild carrot the followi ng spring in Clinton and Lenawee Counties, respectively. EPP applicati ons of 2,4-D ester at 1.12 kg/ha provided 7 and 72% control of overwin tered wild carrot in St. Clair and Lenawee Counties, respectively.