The UGA Weed Science Group has been getting many questions from County Agents regarding DuPont’s new burndown herbicide Leadoff. Here is what we know and do not know:
1) Leadoff 33.4WSG is a mixture of Matrix/Resolve (rimsulfuron – 16.7%) + Harmony (thifensulfuron -16.7%).
2) The typical use rate for Leadoff is 1.5 oz/A at a cost somewhere between $7-8/A
3) Rotation restrictions for common GA row crops are as follows: soybean/cotton = 30 days; corn = anytime; peanut = 45 days.
4) Leadoff is being aggressively promoted by DuPont sales reps as a residual alternative for the control or Palmer amaranth.
5) There has been no research conducted by the UGA Weed Science Group to support or refute these claims.
6) Rimsulfuron does provide some soil residual activity on certain weeds. However, I can find no published data for Palmer amaranth.
7) The current Leadoff label suggests that it will only provide partial control or suppression of Palmer amaranth. http://www.cdms.net/LDat/ld2AA003.pdf
8) I am not sure why would any grower would want only partial control or suppression of Palmer amaranth with Leadoff when other residual herbicides are available that have a proven record of control (i.e. Atrazine, Valor, Dual Magnum, Direx).
9) A few field trials will be conducted by the UGA Weed Science Group this year to figure out what kind of residual control Leadoff actually provides.