New herbicide labels for vegetable crops for 2008
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.
Several new herbicide registrations have been issued for vegetable crops during the past year. Growers should have copies of the labels in their possession before use. Recommendations for most of these uses are included in MSU Extension bulletin E-433, 2008 Weed Control Guide for Vegetable Crops.
Selectmax, the new formulation of Select, a postemergence grass herbicide, has been labeled for the following crops: asparagus, dill, endive, escarole, parsley, pea and Swiss chard. Selectmax normally is applied at 9-16 fl oz per acre. It is similar in activity to other postemergence grass herbicides, such as Poast and Fusilade. It is the most effective of the group against annual bluegrass, which often is a problem early in the season.
Raptor is registered for postemergence broadleaf control in snap beans. It should always be applied in a tank mix with Basagran, which reduces snap bean injury. The combination gives very good control of most emerged grasses and broadleaves.
Prowl H2O is registered for preemergence weed control in carrot. It may be applied at 2 pt/acre after seeding. Prowl H2O also is registered for peas as a preplant incorporated (PPI) treatment. It also may be applied to pepper and tomato before transplanting as a PPI treatment, or to the soil as a pretransplant treatment. It may be applied as a directed spray to the soil after transplanting. Prowl H2O also may be applied to soil before transplanting strawberries. It is not registered for application to established strawberries.
Poast, a postemergence grass herbicide, now is labeled for dill, okra, radish and rutabaga. The normal use rate is 1-2.5 pt/acre. Poast is active against most annual grasses.
Outlook is labeled for preemergence weed control in leek and green onion. It should be applied after the 2 leaf stage to suppress new weed germination. It is effective against most annual grasses and broadleaves, and yellow nutsedge. Outlook does not have postemergence activity, and will not control emerged weeds.
Callisto is registered for preemergence annual weed control in asparagus and rhubarb. In asparagus, it may be applied at 3-7.7 fl oz/acre in the spring before spear emergence. It also may be applied after final harvest. The maximum amount per acre per year is 7.7 fl oz, in one or two applications. Callisto gives good preemergence and postemergence control of most broadleaves. It is weak on most grasses.
In rhubarb, apply 6 fl oz Callisto before rhubarb begins to grow in the spring. If some weeds have germinated, add 1 percent COC to improve postemergence activity.
Chateau is now labeled for use in asparagus. It should be applied at least 14 days before spears emerge to avoid injury to the spears. Apply up to 6 oz product per acre (0.192 lb ai/acre) for control of most annual broadleaves and grasses. It works best in combinations with other preemergence herbicides. Chateau does not give acceptable control of horseweed (marestail), even though it is listed as controlled on the label. Add 1 percent COC or 0.25 percent NIS to the spray mixture to increase postemergence burndown of weeds that have emerged at time of application.
Reflex is now registered for preemergence weed control in snap beans. It should be applied after seeding snap beans for control of most annual grasses and broadleaves. Reflex has been registered for postemergence broadleaf control in snap beans, so this is a label expansion. There is still a limitation of one application of Reflex to a field in two years. It probably will be more useful as a postemergence treatment, since several other herbicides are registered for preemergence use in snap beans.
Two new herbicides are registered for use in sweet corn: Laudis and Impact. Both are HPPD inhibitors, related chemically to Callisto. Both Laudis and Impact may be applied postemergence in all types of corn for control of annual broadleaves and grasses. Some sweet corn hybrids may be sensitive to HPPD inhibitors, so try these herbicides on a small area to determine potential crop phytotoxicity. Other new herbicide labels for vegetable crops may be issued soon, and we will print details in the Vegetable CAT Alert as we receive information.