Cox states the obvious, herbicides open the area for weed invasion; that alone should be cause for reconsideration.

What concerns me is the amount of watershed that will be affected by the herbicides. USGeological Survey has several published reports on water contamination by herbicides and their break-down chemicals. (I think it was one in 1996 that included the Yosemite.) Somebody in BLM needs a basic course in hydrology, especially as concerns water tables -- IMHO, BLM's plans for implementing widespread herbicidal spraying is at best a myopic weed-control effort, and will contaminate the water you and I drink.