Next week, the Environmental Resource Center and project partners will plant a newly constructed insectary, also known as a bug nursery, with the noxious weeds necessary to feed and grow weevils that will be used to fight the spread of spotted knapweed in the valley.
According to a news release from the ERC, the insectary is located at the Sawtooth National Recreation Area headquarters and will serve as a local and free source of the knapweed-munching weevils for the U.S. Forest Service and landowners throughout the valley. Knapweed is one of the most widespread noxious weeds in the valley.
The ERC has been an advocate for the use of non-chemical methods of weed control in public spaces like parks and schools.
It and local partners—the SNRA, the Blaine County Weed Department and the BLM—finalized the location, plan and funding for the insectary during late winter and early spring. Last month, with expertise from BLM Bio-Control Specialist Joey Milan and help from Wood River Land Trust staff and interns, the group constructed a corral to house the bugs. The Land Trust is one of the landowners interested in using the insects on properties it manages.
“The Sawtooth NRA staff, the Blaine County Weed Department and the BLM’s biocontrol program have been great to work with,” said ERC Executive Director Molly Goodyear. “The Sawtooth NRA, property owners and land managers will soon have a locally available resource for fighting knapweed without the use of harmful chemicals. The ERC’s Pesticide Action Team will work to ensure that anyone who wants to control spotted knapweed knows about this chemical-free option.”
All that remains is to plant the interior of the corral with enough spotted knapweed crowns, about 400 plants, to feed the insects and grow enough to begin harvest for biocontrol projects in the community in 2015.
People are sought to help in the planting effort by bringing six to 10 spotted knapweed crowns to the SNRA headquarters, between 3 p.m. and 7 p.m. on Wednesday, June 11, to help plant the insectary. Plants can be up to 6 six inches high and should have about 4 inches of root. To protect the plants, wrap the roots in a moist paper towel during transport.
The corral is a simple rectangular enclosure made of posts and metal flashing encompassing a 25- by 50-foot area behind SNRA headquarters.
The weevils, Cyphocleonus achates, live, eat and reproduce within the enclosure. Because the insects do not fly, the posts hold the metal flashing around the area and the flashing is then folded over at the top. When the weevils do crawl up the flashing and reach the curved top, they fall over back inside the corral.
Thanks to funding from the BLM and the Blaine County Weed Department, educational signs and displays will be constructed on site for the public to learn the details about biocontrol and the insectary.
“It’s very important to have as many tools available as we can to fight one of the worst weeds around, and we expect to begin using these insects in new areas on the Sawtooth NRA as soon as possible,” said Robert Garcia, who manages the weed control efforts at the SNRA. “And we are happy to share the insects because weeds don’t recognize property boundaries.”
Harvest of the insects and distribution to landowners could begin as early as summer 2015. For information on spotted knapweed identification, go to www.idahoweedawareness.net/vfg/weedlist/sknapweed/sknapweed.html.
For more information on the community insectary or the Environmental Resource Center, see www.ercsv.org.