Control of goosegrass and large crabgrass with different preemergence herbicides for the initial and sequential application was studied at four locations in Indiana. Pendimethalin at 1.1 kg ai ha-1 was used as the initial application in all treatments. Sequential treatments applied 6 wk after the initial treatment consisted of: 2.2 kg ha-1 benefin; 1.4/0.7 kg ha-1 benefin/trifluralin; 8.4 kg ha-1 bensulide; 11.8 kg ha-1 DCPA; 0.6 kg ha-1 dithiopyr; 2.2 kg ha-1 oxadiazon; 1.1 kg ha-1 pendimethalin; or 0.6 kg ha-1 prodiamine. Dithiopyr at 0.6 kg ha-1 with no initial application was also included. Highest large crabgrass control ratings were obtained through September with pendimethalin + pendimethalin, pendimethalin + dithiopyr, and dithiopyr alone postemergence. All other sequential applications tested improved control over a single application of 1.1 kg ha-1 pendimethalin, but rarely gave adequate season long control.
