Stem

  • Up to 4 ft. tall, stiff, highly branched, bushy and covered with hairs; NO wings on upper stems
Photo of Purple starthistle

Leaves

  • Alternate; 4-8 in. long, mostly pinnate-divided, covered with short grayish hairs and dotted with resin
Photo of Purple starthistle

Flower

  • 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
Photo of Purple starthistle

Root

  • Deep, stout taproot
Photo of purple starthistle

Other

  • Grows best in sites with heavy, fertile soils; often infests rangelands, waste areas and roadsides; not known to occur in Nevada
  • Annual, biennial or perennial; reproduces by seed; older rosettes have a circle of straw-colored 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
 

Control

  • 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, dicamba, or glyphosate in the rosette stage; aminocyclopyrachlor, aminoyralid, picloram or sulfometuron preemergence to rosette stage 
Blecker, L., Creech, E., Dick, J., Gephart, S., Hefner, M., Kratsch, H., Moe, A., Schultz, B. 2020, Nevada Noxious Weed Field Guide – Purple Starthistle, Extension, University of Nevada, Reno, Field Guide

Learn more about the author(s)

 

Also of Interest:

 
Photo of canada thistle plant.
Nevada Noxious Weed Field Guide – Canada thistle
Canada thistle is a noxious weed that has been identified by the state of Nevada to be harmful to agriculture, the general public, or the environment. Learn more about this weed.
Blecker, L., Creech, E., Dick, J., Gephart, S., Hefner, M., Kratsch, H., Moe, A., Schultz, B. 2020, Extension, University of Nevada, Reno, Field Guide
Photo of malta starthistle plant with yellow and pink and red flowers
Nevada Noxious Weed Field Guide – Malta starthistle
Malta starthistle is a noxious weed that has been identified by the state of Nevada to be harmful to agriculture, the general public, or the environment. Learn more about this weed.
Blecker, L., Creech, E., Dick, J., Gephart, S., Hefner, M., Kratsch, H., Moe, A., Schultz, B. 2020, Extension, University of Nevada, Reno, Field Guide
photo of perennial sowthistle patch
Nevada Noxious Weed Field Guide – Perennial sowthistle
Perennial sowthistle is a noxious weed that has been identified by the state of Nevada to be harmful to agriculture, the general public, or the environment. Learn more about this weed.
Blecker, L., Creech, E., Dick, J., Gephart, S., Hefner, M., Kratsch, H., Moe, A., Schultz, B. 2020, Extension, University of Nevada, Reno, Field Guide
Photo of yellow starthistle plant
Nevada Noxious Weed Field Guide – Yellow starthistle
Yellow starthistle is a noxious weed that has been identified by the state of Nevada to be harmful to agriculture, the general public, or the environment. Learn more about this weed.
Blecker, L., Creech, E., Dick, J., Gephart, S., Hefner, M., Kratsch, H., Moe, A., Schultz, B. 2020, Extension, University of Nevada, Reno, Field Guide
Photo of iberian starthistle plant with pink flower on top
Nevada Noxious Weed Field Guide – Iberian starthistle
Iberian starthistle is a noxious weed that has been identified by the state of Nevada to be harmful to agriculture, the general public, or the environment. Learn more about this weed.
Blecker, L., Creech, E., Dick, J., Gephart, S., Hefner, M., Kratsch, H., Moe, A., Schultz, B. 2020, Extension, University of Nevada, Reno, Field Guide
 

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Integrated Pest Management

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