Widely spread across Utah. Control efforts focus on reducing or eliminating new or expanding populations.
Quick Facts
Report your sighting through EDDMapS to help us track and respond to new infestations.
Report on EDDMapSMusk Thistle
Carduus nutans
Overview
Musk thistle is a biennial plant from Eurasia that invades rangelands, roadsides, and disturbed areas. Each plant can produce up to 120,000 seeds. It forms dense stands that reduce forage production and are avoided by livestock due to its spines.
How to Identify
Biennial 2-6 feet tall. Large, nodding rose-purple flower heads (2-3 inches across). Deeply lobed, spiny leaves with continuous spiny wings along the stem. Distinctive musty fragrance.
Control Methods
Biological control using a seed-head weevil (Rhinocyllus conicus) is effective. Hand-pull or cut rosettes below the soil surface. Herbicide treatment on rosettes.
Herbicide Recommendations
Clopyralid, picloram, or 2,4-D applied to rosettes in fall or spring. Biological control (Rhinocyllus weevil) is recommended.
⚠️ Always read and follow pesticide label directions. Contact your county weed superintendent for site-specific recommendations. Permits may be required near water.
Need help managing this weed?
Skyline CWMA can connect you with technical assistance, cost-share programs, and licensed contractors for treatment on your property.
