Crabgrass on the rise
Editor’s note: This article is from the archives of the MSU Crop Advisory Team Alerts. Check the label of any pesticide referenced to ensure your use is included.
Now that we’re on the verge of summer officially beginning, crabgrass has really started to show its presence in turf. If you skipped a preemergence herbicide application to control crabgrass and are now considering control options the best plan of attack is to go after the crabgrass plants while they are still fairly young.
Metharsenate (MSMA) was the standard in the industry for years. It is no longer available. If you still have some inventory, you may use it. It will likely take two applications (higher temps equal better control).
Fenoxaprop-p-ethyl (Acclaim Extra) provides good to excellent crabgrass control up to the three-tiller growth stage. Fenoxyprop offers improved efficacy and turf safety over MSMA. As crabgrass matures or becomes drought stressed, the efficacy of this product decreases. Fenoxyprop-p-ethyl (Acclaim Extra) is not commonly used with 2,4-D as this combination can result in poor weed control and significant cool-season turfgrass injury. The label suggests waiting at least seven days between applications of 2,4-D and Acclaim Extra.
Quinclorac (Drive) may be tank mixed with 2, 4-D or products containing 2, 4-D without antagonism. The added benefit is that there appears to be synergism between 2, 4-D and quinclorac. Quinclorac will control crabgrass beyond the three-tiller growth stage with a single application. Quinclorac also has stand-alone postemergence activity on certain broadleaf weeds, including dandelion, clover, bindweed and speedwell. MSU research has shown increased weed control activity of several broadleaf herbicides by tankmixing them with quinclorac. Increased activity has been seen on ground ivy, speedwell, violets, dandelion, and clover. Products containing 2, 4-D have benefited the most from this combination. These combinations deserve consideration to be used for callbacks and mid-to late-summer weed control applications
Dr. Frank’s work is funded in part by MSU‘s AgBioResearch.