County releases toadflax insects in the Roaring Fork Valley
In late May, Garfield County Vegetation Management received 2400 insects from the Colorado Department of Agriculture's Insectary in Palisade, to assist in the effort to manage the county-listed noxious weed Dalmatian toadflax.
Dalmatian toadflax is an invasive, deep-rooted perennial forb that crowds out native vegetation.
It is prevalent in and around Glenwood Springs, including the Red Mountain area, West Glenwood, and along Three Mile Road.
The insects are stem boring weevils, Mecinus Janthinus, and have a good track record for helping reduce the populations of Dalmatian toadflax throughout Colorado and the west. The adult weevils feed on the leaves and stems, and the larvae will mine the stems. The weevils generally don't kill the entire plant, however, they do suppress flower formation, resulting in the reduction of plant populations. The weevils have been helpful in managing the toadflax infestations in the Red Mountain area.
All insects distributed by the insectary have been exposed to strict screening and quarantine procedures, before they are allowed for release. These weevils originate from Europe and south-western Russia, also the original home of Dalmatian toadflax.
These bio controls are especially helpful in inaccessible areas, and on sites located near riparian areas.
Local ranchers, Sandy Jackson, a Mount Sopris Conservation District board member, and her husband, Jim Campbell, are shown here, releasing the insects on their ranch south of Glenwood Springs.