Command 3ME for preemergence weed control in vegetable crops
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.
Command 3ME (clomazone) has been registered for a number of vegetable and field crops for many years. It is an excellent preemergence grass herbicide and also controls several broadleaves, including velvetleaf, common lambsquarters, common ragweed and smartweeds. It has fair to good activity against white campion (cockle) and annual morning glory. The original formulation, Command 4 EC, was relatively volatile and had to be incorporated into the soil immediately after application. Even with incorporation, there were a number of situations in which clomazone moved off site and caused bleaching and whitening of neighboring plants. In most cases, the bleaching is temporary and green color returns in one to two weeks, but in some cases there was serious plant injury.
The current formulation, Command 3ME, is less volatile than the 4EC formulation. The ME uses micro encapsulation technology to surround the active particles with inactive carrier. This allows the 3ME formulation to be applied to the soil surface rather than be incorporated. However, by the nature of the chemical, there is still reason for caution to avoid movement off site and potential liability for damage to neighboring crops or ornamental plants. Most problems arise after application during windy weather.
The Command 3ME label contains the following restrictions: Do not apply Command 3ME within 1,200 feet of the following areas: Towns and housing developments; commercial fruit, nut or vegetable production (except for other registered crops); or commercial greenhouses or nurseries. Before application, determine air movement and direction; do not apply in winds above 10 mph; do not apply Command 3ME to non-field areas including fence rows, waterways, ditches and roadsides. When moving spray equipment to noncontiguous sites, do not allow spray solution to spray or drip from tanks, hoses, fittings or spray nozzles and tips.
Command is a valuable herbicide and is critical for weed control programs in several crops, including beans, cabbage, cucurbits, peppers, peas, sweet potatoes and mint.
Judicious use of this herbicide will result in continuance and expansion of the label. Abuse may result in withdrawal of some of the labels. Applicators should apply Command only during low wind conditions, preferable under 5 mph. Large-droplet nozzles and drift control additives will help avoid drift off site. Moisture, either irrigation or rain, after application will help move it into the soil and activate its weed control activity, as well as reduce movement off site. Command 3 ME should not be preplant incorporated.
The bleaching effects of Command make it an easy target for activist neighbors. By using it correctly, we can avoid drift and the hard feelings that may accompany its use.