Ranchland managers who have long worried about the quality of forage available for their livestock have a new tool to fight the invasive annual grasses medusahead and ventenata. Esplanade 200 SC (19.05% indaziflam), a pre-emergent herbicide from Bayer, has received a Section 18 Emergency Exemption in Montana, Wyoming and Utah for use on rangeland, pasture and Conservation Reserve Program (CRP) acres.
"These two grasses are even more devastating than cheatgrass, mainly due to extremely low forage value and because they will out-compete the cheatgrass," said Harry Quicke, Bayer western vegetative management stewardship and development manager. "More than 7,000 acres of Wyoming rangeland have been sprayed to stop the spread, and more needs to be done to safeguard land in these states."
It is important to locate these new invaders and to treat them before they spread and further degrade rangeland habitat. In the past, herbicide treatments have been inconsistent or only provided control for a short period of time. Esplanade herbicide is changing that. The pre-emergent herbicide is showing control over multiple years with just one application.
Justin Hossfeld, Out West LLC agricultural management specialist said, "On rangeland specifically, control of medusahead and ventenata means improvement of forage and yield. Where we have used Esplanade, we doubled the total digestible nutrients in our treated sites. We have been able to maintain open space and allow desirable grasses to grow. In fact, in the treated areas, I don't have to use feed supplements at all."
Quicke added that it's rewarding to be part of restoring desirable perennial grasses, forbs and shrubs to infested rangeland and natural areas. "For the first time we can deplete the annual grass seedbank, reduce wildfire risk and give desirable perennial grasses, forbs and shrubs the opportunity to grow."
The Emergency Exemption allows for one foliar application of Esplanade per year applied by ground boom, backpack sprayer or aerial equipment at a single rate of 5 fl. oz/A, per year. Livestock are not allowed to graze in treated areas within two weeks of treatment.
Invasive annual grass such as cheatgrass, medusahead and ventenata are spreading at an alarming rate and pose a major threat to western rangeland and natural areas. When invasive annual grass dominates a landscape, the result is more frequent wildfires, degraded wildlife and pollinator habitat, as well as the loss of ecosystem diversity.
Annual grass increases wildfire frequency because the fine fuels on the ground steadily increase every year. "Wildfires will severely injure or kill desirable perennial species and they don't have time to recover," Quicke said. "In a very short period of time these sites can turn into a near monoculture of annual grass. It is very difficult and expensive to re-establish desirable species on these severely degraded sites. We recommend prioritizing invasive annual grass control on sites that still have viable populations of desirable perennial grasses, forbs and shrubs."