The Bureau of Land Management and the Moffat County 4-H Cloverbuds released Sunday evening biological control insects on invasive salt cedar 35 miles southwest of Craig, near Duffy Mountain.
"Salt cedar, also called tamarisk, is a non-native, invasive tree that establishes itself very densely along drainages, creeks and rivers, crowding out important native species of cottonwood, willow, grasses and forbs," the BLM reported in a news release.
The tree's extensive root systems accumulate salts from the soil, and when the salt concentrated leaves are dropped on the soil, limit the growth of other competitive desirable vegetation.
The release occurred on BLM lands along the Yampa River, up from the Duffy Mountain river access point.
Assisting with the release were the Moffat County 4-H Cloverbuds.
"This is a group of pre-4-H kids, ages 5 to 7 years old, that use hands-on learning activities to explore art, plants and animals, science, and the environment," the BLM stated in the release. "These kids engage in group activities that promote personal development, healthy lifestyles, and a sense of citizenship."
The biological control agent, Diorhabda elongata, was brought from Asia where it is a native predator of salt cedar.
After years of lab testing, the insect has successfully established in Colorado through biocontrol release programs, the BLM reported.
The beetles are selective insects that forage only on salt cedar.
Repeated defoliation of the trees by these natural predators provides a level of control comparable to herbicide or mechanical treatment at a portion of the cost.
"We're very excited to release these insects on BLM land in Northwest Colorado and establish populations to control the salt cedar invasion," said Christina Rhyne, BLM rangeland management specialist, in the release. "It's also great to have the opportunity to have the kids help and talk to them about the impact of weeds and public lands in our area."