tamarisk

Tamarisk beetle
RiversEdge West / CC BY 2.0

CLARKDALE, Ariz. (AP) - Matt Johnson treks along an Arizona riverbank and picks out a patch of yellow-tinged tamarisks. He sweeps a cloth net across the trees, hoping to scoop up beetles that munch on their evergreen-like leaves.

He counts spiders, ants and leafhoppers among the catch and few beetles or their larvae.

Jose Hernandez / USDA-NRCS PLANTS Database

In an open field in Longmont, Colorado, about a dozen people crouched in the tall grass, moving slowly and deliberately through mud that squelched underfoot. Some carried huge, serrated knives called hori-hori, a Japanese tool made specifically for gutting weeds. Others wielded gardening shears, saws or chemical sprays as their weapons of choice.