Scouts are sent out on foot, in vehicles, and on horseback to find infested sites. Although the tiny WW seeds can be spread by wind or water, people are probably the chief means of dispersal. To prevent the spread of this pest, agricultural quarantines specify conditions for moving soil, plants, or machinery out of infested areas. Ongoing research provides information on the best chemical or combination of chemicals for the given crop, weed species, and field conditions. Eliminating the microscopic seeds is another important part of eradication.
Some seeds die of natural attrition or sprout only to be killed by a herbicide.
However, since WW seeds can persist in the soil for a decade, efficient eradication requires accelerating the natural rate of seed germination. WW seeds can be eliminated from the soil by creating conditions so they germinate when no host is present. This phenomenon is known as suicide germination. Ethylene gas, a natural ripening agent produced by fruits, vegetables, and flowers, is injected into the soil under proper environmental conditions. It stimulates seed germination, but lacking a host the seedlings die.