In this Issue:
- Controlling Invasive Weeds Is Key to Restoration
- Extending Rimsulfuron Use
- Fuel for Wildfires
- DuPont™ PrecisionPac™ Dispensing System
Controlling Invasive Weeds Is Key to Restoration
With the frequency of major wildfires in western regions of the country jumping from once every few decades to every three or four years, land managers play an important role in reversing this destructive cycle. Unfortunately, each time a wildfire occurs, there is even greater likelihood it soon will be followed by an even larger, more intense blaze.
"These fires become a vicious cycle," says Steve Dewey, Ph.D., invasive weeds specialist, Utah State University. "Highly flammable cheatgrass tolerates fire well and reestablishes quickly from viable seeds in the soil. When cheatgrass regrows, it forms an even denser weed community, ready to ignite and spread fire quickly. These aggressive weeds also choke out regrowth of desirable plants. This cycle will not reverse itself naturally.
“Weed management is key to stopping the wildfire cycle,” says Dewey, who worked as a firefighter for six summers to better understand the nature of wildfires and gain greater insights on weed management. He discovered a direct parallel between the principles of fire management and effective weed control.
"Both fire control and weed management are based on four cornerstones: prevention, detection, control and restoration," Dewey notes. "This weed management model is being adopted by federal, state, local and private land managers. It helps land managers think more broadly about weed management and how to change land conditions to no longer favor weeds."
The four key elements in Dewey's model, if applied to a cheatgrass management program, would look like this:
1. Prevention --- Follow land management practices that favor optimal growth of native plants and prevent introduction of cheatgrass seeds. These practices include moderate grazing systems and limiting mechanical disturbances, such as road construction. Applying herbicides to control known weed infestations on adjacent areas is also important.
2. Detection --- Knowing what vegetation is already established is key to managing invasive weeds. Scouting, inventorying or mapping land will help locate new infestations early, for easier, small-scale control and to prevent weeds from spreading to non-infested areas.
3. Control --- When cheatgrass is detected, herbicides can play a critical role in eliminating growing weeds and weed seeds, so desirable plants can thrive. Select a herbicide that will kill cheatgrass, but won't harm desired species.
4. Restoration --- The goal of restoration is to reestablish native plants and/or introduce new, desirable vegetation. By controlling invasive weeds, desirable plant seedlings will be able to establish more quickly and help suppress further weed growth.
RESEARCH AND DEVELOPMENT UPDATE
Extending Rimsulfuron Use
The combination of the DuPont active ingredient, rimsulfuron, with chlorsulfuron is being tested to evaluate its effectiveness in control of cheatgrass and medusahead as well as other broadleaf annuals in the arid West. Research to date has demonstrated effective weed control, which could provide another tool for rangeland restoration. Rimsulfuron currently is labeled for use on potatoes, tomatoes, field corn, grapes and tree fruit crops.
Watch for more information about using rimsulfuron and chlorsulfuron for invasive weed control in future issues of Weed Wise.
INVASIVE WEED FOCUS
Fuel for Wildfires
Cheatgrass (downy brome) is a highly flammable invasive weed that adds fuel to wildfires. The soft, dense hair covering the mature noxious weed, plus its ability to produce more than 10,000 plants per square yard, enable cheatgrass to increase fire intensity and keep fires burning.
Cheatgrass thrives in areas that have undergone construction, fire and floods or have been heavily used, but it will invade undisturbed grasslands as well. An annual plant that establishes early in the season before native species emerge, cheatgrass can grow up to 30 inches tall. With die-down in early summer, cheatgrass becomes an extreme fire hazard for the remainder of the season.
The most successful control method for this dangerous weed is a combination of ongoing cultural and chemical treatments to ensure eradication of the seed from the soil. DuPont™ Landmark® XP herbicide provides long-lasting, broad-spectrum control of cheatgrass and medusahead. Providing several years of control, Landmark® XP allows grass replanting and non-cropland restoration by reducing broadleaf weed invasion. The addition of DuPont™ Telar® XP herbicide adds residual control on many winter and summer annual weed species during the restoration period.
DuPont™ PrecisionPac™ Dispensing System
Precise mixing control for each sprayer load is at your fingertips with the easy-to-use DuPont™ PrecisionPac™ Dispensing System.
Five simple steps load premeasured herbicide into your sprayer:
1. Identify the weed(s) you want to control
2. Select a herbicide
3. Determine the proper application rate
4. Calculate the number of ounces needed per load
5. Press the selection buttons
The PrecisionPac™ Dispensing System provides ultimate flexibility, allowing you to quickly create customized herbicide solutions for every load. And measurement is always precise and dependable, since the system can dispense from 2 to 64 ounces in 1/10-ounce increments.
By dispensing only the product needed for the task at hand, you eliminate waste, maximize your herbicide budget and support sound stewardship. Ask your DuPont representative for more information about incorporating the PrecisionPac™ Dispensing System into your invasive weed control program.