Stem

  • Up to 6 ft. tall, semi-woody, waxy and lacks hair (glabrous); many stems can arise from each crown; often branched near top; branches arise from leaf axils
Photo of perennial sowthistle patch with yellow flowers
 

Leaves

  • Alternate; upper leaves are smaller and fewer than lower leaves; leaf bases clasp the stem; exude white, milky sap when broken
  • Edges (margins) smooth to deeply lobed and spiny
Photo of perennial sowthistle leaf
 

Flower

  • Yellow; less than 2 in. wide; base of flower is vase shaped; flower base and stalk usually covered with stiff, sticky hairs
Photo of perennial sowthistle yellow flower
 

Root

  • Creeping root system
Photo of perennial sowthistle plant with root

Other

  • Grows best in moist, fertile soils; often infests crop fields, gardens, waste areas and ditch banks; known to occur in Washoe and White Pine counties
  • Perennial; reproduces by seed and roots; seed is wind-dispersed
 
 

Control

  • Tilling and mowing not effective; pulling can be effective, but the entire root must be removed. Preventing seed production is essential for control
  • Apply 2,4-D, aminopyralid, clopyralid, MCPA, or picloram to actively growing plants before bud stage
Blecker, L., Creech, E., Dick, J., Gephart, S., Hefner, M., Kratsch, H., Moe, A., Schultz, B. 2020, Nevada Noxious Weed Field Guide – Perennial sowthistle, Extension, University of Nevada, Reno, Field Guide

Learn more about the author(s)

 

Also of Interest:

 
Needs Assessment for Noxious Weeds in Churchill County: Part 4 of 5 - Criteria for Herbicide Use and Selection
This fact sheet is the fourth in a series of five that reports the results of a needs assessment survey completed by faculty in University of Nevada Cooperative Extension (UNCE). The survey attempted to identify the major issues related to the management and control of weeds in N...
Davison, J., Powell, P., Schultz, B., and Singletary, L. 2012, University of Nevada Cooperative Extension
Nevada’s Priority Agricultural Weeds: Hoary Cress
Plants commonly referred to as hoary cress (Cardaria sp.), or short whitetop, are one of three different but closely related perennial forbs. The Cardaria species are widespread across all eleven Western states, including every county in Nevada.
B. Schultz, S. Foster 2021, Extension, University of Nevada, Reno, SP-21-03
African mustard plant
Nevada Noxious Weed Field Guide – African mustard
African mustard 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., H. Kratsch, Moe, A., Schultz, B. 2020, Extension, University of Nevada, Reno, Field Guide
Photo of common crupina stem
Nevada Noxious Weed Field Guide – Common crupina
Common crupina 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 Common St. Johnswort plant
Nevada Noxious Weed Field Guide – Common St. Johnswort
Common St. Johnswort 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
 

Associated Programs

Master Gardeners at tabling event

Master Gardeners of Nevada

Program trains local gardeners to provide research-based horticulture information to Nevadans

ladybug larva eating aphids on a pepper plant

Integrated Pest Management

Integrated Pest Management program is a long-term management strategy that uses a combination of tactics to reduce pests to tolerable levels with potentially lower costs for the pest manager and minimal effect on the environment.

Weed Warriors Invasive Weed Training cb

Weed Warriors Invasive Weed Training

The Weed Warriors program tackles the growing problem of weeds on public and private land.