RESEARCH TRIANGLE PARK, N.C. – The Arkansas State Plant Board has granted Ricestar HT Herbicide a 24(c) special local needs label for use rates up to 24 ounces during the 2005 growing season.
“We’re excited about the approved new use for Ricestar HT,” said Andy Hurst, Ricestar HT product manager, Bayer CropScience. “The 24(c) will provide even more flexibility to growers in controlling all the major grass weeds in rice. The higher use rate will improve consistency of control when grasses are large or in heavy populations, as well as when environmental conditions are less favorable.”
Additionally for 2005, Bayer CropScience will introduce new, cost effective pricing to accommodate the higher use rates for Ricestar HT.
Ricestar HT has a weed control spectrum that includes barnyardgrass, broadleaf signalgrass, fall panicum, johnsongrass and sprangletop.
“Ricestar HT has always been an excellent herbicide in our trials,” said Ford Baldwin of Practical Weed Consultants, Austin, Ark. “By raising the rate, growers will be able to increase their control of larger grasses prior to flood and also improve the consistency of their tankmixes.”
The 24(c) allows for use rates of 17 to 24 ounces per acre. Lower rates should be used for small one- to three-leaf grass weeds in good growing conditions. Higher rates should be reserved for larger grass weeds up to two tillers or when grass pressure is heavy.
Rates greater than 17 ounces should be used only on rice that has at least four leaves, Hurst said. Only one application at the 17- to 24-ounce rate is permitted and Ricestar HT should be applied at least 14 days before panicle initiation.
“In less than ideal pre-flood conditions, where there’s a mix of grass populations or larger grasses are present, Ricestar HT at the higher rates has been more consistent,” said Ken Smith, Extension weed scientist, Southeast Research and Extension Center, University of Arkansas.
“Growers aren’t always able to get in the field the day the ground is wet and growing conditions are ideal. The rate range to higher rates will offer flexibility we haven’t had before.”
Because it is highly selective for grass weeds, Ricestar HT will not cause injury to adjacent broadleaf crops, Hurst said. The herbicide provides excellent tank-mix flexibility with partners including Aim, Command, Facet, Permit and others. Ricestar HT can be used after a pre-emergence herbicide application or early post with Command or Facet for broader spectrum activity and residual control. It’s also effective on both Facet- and propanil-resistant barnyardgrass, he added. Consult the product label for specific tank-mix recommendations.
“We appreciate the cooperation with our university cooperators, the Arkansas State Plant Board, consultants and agronomists in the evaluation of Ricestar HT for this use,” Hurst said. “Their efforts have made it possible for growers to utilize this important rice tool in a new and more effective way for the 2005 season.”
Bayer CropScience will support similar 24(c) requests that currently are being organized in Louisiana, Missouri and Mississippi for the 2005 season.