The graph shows that most woolly cupgrass emergence occurred more than two weeks ahead of giant foxtail. This represents one more competitive advantage for woolly cupgrass. The emergence pattern study may have been inadequate to detect extended emergence under field conditions, since seeds were planted at only the two-inch depth, and the same number of seeds were planted for each species. In a woolly cupgrass-infested field, seeds from deeper in the soil would likely emerge later, extending emergence. Other biological traits help make woolly cupgrass a competitive weed.
Seedlings initiate tillering at the two or three leaf stage and produce many tillers.
One study showed that woolly cupgrass produces more leaves, leaf area, tillers and total biomass than giant foxtail. In addition, studies have shown that woolly cupgrass has a higher level of tolerance than giant foxtail to many commonly used herbicides. Woolly Cupgrass Management Prevention Preventing the spread of woolly cupgrass to uninfested fields is by far the simplest and most effective control strategy. Woolly cupgrass is moved from field to field by farm machinery, moving water and birds. Growers should take special care to avoid moving seeds in combines and in soil clinging to tires and tillage equipment.