Weed Management

Giant miscanthus (Miscanthus x giganteus) is a perennial nonnative grass hybrid that is being investigated as an alternative crop in Maryland. Although the invasive potential of this species appears to be low, there is little information about how to manage giant miscanthus should it become weedy, or should another crop be desired following miscanthus production. Therefore, studies were conducted to evaluate control methods for giant miscanthus in two agronomic settings (discing and no-till) as well as herbicide options for riparian settings. Results indicated that multiple herbicide treatments or mowing followed by herbicide treatments over successive years would be needed to eliminate giant miscanthus. Authors: Kurt Vollmer and Ellie Rogers; Considerations for Terminating Giant Miscanthus on Maryland Farms (FS-2023-0685).

Palmer amaranth, Amaranthus palmeri, is a new invasive weed in the pigweed family that has become a major challenge for farmers across the U.S. for much of the last decade. Native to the Sonora Desert of Arizona and Northern Mexico, Palmer amaranth is well adapted to the hot Maryland summers. It was first discovered in Maryland during the mid-twentieth century, but the presence of herbicide resistant Palmer amaranth was not confirmed until 2014. Since then it has spread to most regions of the state including Eastern, Southern, and Western Maryland. The spread of Palmer amaranth has been hastened by the movement of contaminated equipment, feed, and seed from infested areas.

Yellow, green, and giant foxtail are the three most common weedy foxtail species in Maryland. Knowing the differences between foxtail species and look-alike grassy weeds can assist with identification, and the selection of effective weed management strategies. Title: Know Your Foxtails (FS-2023-0658); Authors: Dwayne D. Joseph, and Leo Kerner