New 24c label allows higher rate on high organic soils.
Prowl H2O herbicide is now labeled for preemergence weed control in green onions. The Section 3 Supplemental Label for use on green onions was issued in July 2013. This label allows application of Prowl H2O at the rate of 2 pints (0.95 pounds a.i.) preemergence on all soils. A second application may be made at the two to three leaf stages of green onions. The two applications must be separated by 30 days and the preharvest interval for the last spray is 30 days.
This label includes all crops in the green onion crop group, which includes chives, leeks, spring onions, scallions, Japanese bunching onions, green shallots and green eschalots.
In addition to the Section 3 Supplemental Label, in April 2014, Michigan Department of Agriculture and Rural Development issued a Section 24c SLN label for use of Prowl H2O at a higher rate preemergence on high organic soil. Under the new label, Prowl H2O may be applied preemergence after seeding at a rate of 3-4 pints per acre (1.43-1.9 pounds a.i.). On high organic soils, Prowl H2O is less effective at the lower rate.
The new label allows use of sufficient Prowl H2O for good weed control for six to eight weeks, which should be most of the growing cycle of green onions. This label allows use of the full per acre rate preemergence rather than as a split application. This 24c label also includes the group crops listed above.
Growers should have copies of both labels in their possession when applying Prowl H2O to green onions. For more information, contact Michigan State University Extension specialist Bernard Zandstra at zandstra@msu.edu.
Source : msu.edu