Leafy Spurge
The Sheridan County Weed and Pest District (SCWPD) treats leafy spurge (Euphorbia esula L.), within our Special Management Program (SMP). This program offers 100% cost share for chemical to landowners who choose to treat leafy spurge on their property. Participating landowners must develop a management plan with a member of SCWPD staff and abide by the terms of our Leafy Spurge Management Agreement.
The above image shows leafy spurge infesting a rangeland near Clearmont
Why Leafy Spurge?
Leafy spurge is an invasive forb that was brought to the U.S. from Eurasia through impure seed processing. This weed has taken over Sheridan County, especially targeted in the eastern half. It reproduces by seed and new shoots from the existing roots of adult plants. It is known for having a high content of milky white sap that can cause irritation to the mouths of cattle. This weed drastically decreases the forage quality of infested rangelands, is unpalatable, and is difficult to control. SCWPD uses an Integrated Pest Management (IPM) system which utilizes multiple methods of control in order to most effectively control leafy spurge and minimize desirable plant damage.
The above image shows the pink shoots coming from the roots of a leafy spurge plant that will grow to become new plants
The above image shows the white sap coming from the stem of a Leafy spurge plant, which can cause irritation
Methods of Control
Chemical
The chemical control methods used include aerial and ground spray treatments. SCWPD contracts out an aerial spray crew to move in unison with summer seasonal spray crews to reduce the spurge populations on designated lands. The seasonals use 4-wheelers and side-by-sides to best cover the accessible places, while the aerial team gets the more rough terrain. A number of herbicides are used depending on the site description, time of year, and type of application. This all done with the goal of reaching the most effective and safest control of leafy spurge possible.
The above video shows the goats moving through a patch of spurge and selecting for it while grazing.
Targeted Grazing (biological)
The targeted grazing sector of this program uses goats. These goats are herded by a contractor and her crew. Goats are not affected by the sap of leafy spurge plants and they acquire a taste for the weed which makes them the ideal grazers, sheep being the second most effective. During a grazing project, the goats get herded into patches of leafy spurge and held there until it is grazed down to the ground. Then they get moved to the next patch. Currently SCWPD has 10 landowners participating, where they will get their spurge grazed once each summer. This process reduces the number of leafy spurge seeds being added to the ecosystem and drastically weakens the plants. If leafy spurge is consistently grazed all season long it has been shown to kill the plants completely.
For more information on getting your leafy spurge grazed or using your goats for weed control please contact our office.
The above picture shows the flower and bract structure of a leafy spurge plant
The above image shows the SCWPD's board members watching the goats graze leafy spurge.
Leafy Spurge Beetles (biological)
The flea beetles Aphthona lacertosa and Aphthona nigriscutis naturally consume leafy spurge in their native habitat. In North America these beetles only consume leafy spurge while leaving all other plants alone. This interaction makes them an excellent control method for leafy spurge. SCWPD actively distributes these beetles to over 80 landowners throughout the summer season. The amount of beetles distributed to each landowner depends on the acreage of infested land they own. The beetles are cost shared 100% to individuals with active Leafy Spurge Management Agreements, which are linked at the top of this page. Beetles are an important tool that need to be monitored for effectiveness both by the land manager and SCWPD. We ask that all beetle releases in the county are tracked using the instructions linked below. Most beetles distributed come from a company out of Montana but a percentage of them are locally collected by the SCWP team. Landowners are paid $25 for every beetle collection (1 cup of ~1000 beetles) made by SCWP on their property.
For more information or to be apart of our beetle distribution list please contact our office.
For our informational handout on the use of beetles click here
The above image shows SCWP's beetle collecting equipment including a sweep net and collection funnel.
The above image shows 1 beetle release (~1000 beetles) collected at an established insectary in Sheridan County