Many factors make weed management on federal public lands an interesting challenge.

In September I was invited to join one of the Sierra National Forest Rangeland Management Specialists to explore a medusahead infestation in one of the grazing allotments she manages. The infested meadow used to be a homestead, though the only obvious reminder is the cluster of still-productive apple trees in the middle of an otherwise grass-dominated site. Pines and other conifers border the meadow, and a forest road divides the meadow into two parts. The portion uphill of the road is steeper and has more trees interspersed with the herbaceous vegetation, while the downhill portion is a more expansive, gentler sloping meadow. Due to the...