Woolly cup grass (Eriochloa villosa (Thunb.) Kunth) is an invasive plant that can compete with crops, especially corn and soybean, and reduces crop yield.  It has become well established in the midwest United States where it is an economic concern for corn and soybean farmers. It is more challenging to control than other annual grasses. Targeted herbicide applications may be required to keep the weed in check.