Stem

  • 1-3 ft. tall, stiff, wiry and usually branched; wings less than 0.1 in. wide created by leaf bases that extend down the stem 
Photo of malta starthistle plant with pink and white flowers
 

Leaves

  • Gray-green, 0.75-6 in. long and densely covered with fine hairs; rosette leaves are oval to strap-like (linear) with smooth to deeply lobed edges (margins); stem leaves are alternate, strap-like to oblong with smooth, toothed or wavy edges
Photo of green leaf plant
 

Flower

  • Yellow, located at branch tips or axils in groups of 1-3; base of flower is vase-shaped, 0.3-0.6 in. diameter and covered with cotton-like hairs and stout, purple-to-brown colored spines 0.2-0.6 in. long
Photo of malta starthistle plant with yellow flower and red and pink thorns.
 

Root

  • Shallow taproot
Photo of green malta star thistle plant

Other

  • Grazing, mowing, burning and cultivation can be effective if done prior to seed production
  • Apply 2,4-D, dicamba or triclopyr to actively growing plants; aminocyclopyrachlor, aminopyralid, clopyralid or picloram pre- or post emergence 
 

Control

  • Repeated hand-removal can be effective; disturbances such as fire, tillage and grazing often promote mustard growth.
  • Apply 2,4-D, glyphosate or triclopyr post-emergence; chlorsulfuron or imazapic pre- or post emergence.
Blecker, L., Creech, E., Dick, J., Gephart, S., Hefner, M., Kratsch, H., Moe, A., Schultz, B. 2020, Nevada Noxious Weed Field Guide – Malta starthistle, Extension, University of Nevada, Reno, Field Guide

Extension Associated Contacts

 

Also of Interest:

 
Date Palm Gardening Guide for Southern Nevada
This publication is a companion to the publication, in Southern Nevada publication. It is a month by month guide to fertilization, pruning, irrigation and other cultural practices for the date palm.
Robinson, M. L. 2002, Extension University of Nevada Reno, FS-02-99
The Date Palm in Southern Nevada
The true date palm, Phoenix dactylifera grows in the desert region and is one of the most popular landscape plants for homes and is uniquely adapted for fruit production and ornamental purposes. This publication focuses on growing the date palm in home and commercial landscapes a...
Robinson, M. L., Brown, B., and Williams, C. F. 2002, Extension, University of Nevada Reno, SP-02-12
Date Palm Tree
Date Palm Gardening Guide for Southern Nevada
This publication explains month-by-month steps for growing date palms in Southern Nevada.
Robinson M.L. 2002, Extension, University of Nevada, Reno
 

Associated Programs

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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.

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Master Gardeners of Nevada

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

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Grow Your Own, Nevada!

Learn the secrets of high desert gardening