Up to 4 ft. tall, stiff, highly branched, bushy and covered with hairs; NO wings on upper stems
Alternate; 4-8 in. long, mostly pinnate-divided, covered with short grayish hairs and dotted with resin
Pink to purple, each located at the tip of a branch; base of flower is vase-shaped, 0.75-1 in. long, 0.25 in. wide and covered with stout, straw-colored spines 0.4-1 in. long
Deep, stout taproot
Grows best in sites with heavy, fertile soils; often infests rangelands, waste areas and roadsides; known to occur in Pershing County
Annual, biennial or perennial; reproduces by seed; older rosettes have a circle of strawcolored spines at the center
Closely resembles Iberian starthistle in everything except seed; seed of Iberian starthistle has plume of bristles extending from one end, purple starthistle does NOT
Mowing plants in bud to flower stage can reduce seed production; repeated hand removal can be effective; DO NOT burn
Apply 2,4-D, clopyralid or dicamba in the (rosette) stage; apply picloram from (rosette) through mid-bolt stage