Javascript is required to view this site. Skip to main content
Text:    -   | Translate
A-Z Index
Locations
Permit Payments  
Inspection Reports
Report a Problem
Menu

Dalmatian Toadflax

Information

Linaria dalmatica - Scrophulariaceae Family - Short-lived perennial

dalmation_toadflax_1_tile   dalmation_toadflax_2_tile  dalmation_toadflax_3_tile  dalmation_toadflax_4_tile     

Identification

  • Flowers:  Flowers are bright yellow snapdragons arranged at the top of the stems.
  • Seeds: Seeds are viable for up to 10 years and one mature plant is capable of producing 500,000 seeds in a year.
  • Leaves:  Leaves are bluish-green with a waxy coating, heart-shaped and close to the stem.
  • Flowering Time:  June – October after the first year.
  • Life cycle:  Short lived perennial with most populations living an average of 3-5 years. 

Impacts

  • Aggressive and invasive species that reduces the value of rangeland, forests, and meadows by out-competing desirable forage species.
  • Unpalatable to livestock.
  • Dalmatian toadflax has an extensive root system that allows it to survive adverse soil and/or climatic conditions and then spread during more favorable years.

Control

Most effective control methods

  • For small infestations, hand pulling or digging up the roots for an average of 6 years. This depletes the root reserves on small patches and prevents further seed production. However, the roots are deep and extensive, and plants will re-sprout from root fragments. 
  • For large infestations or where digging is not practical, apply herbicides in the fall.  Herbicide success can be variable.
  • Use of a non-selective herbicide (such as glyphosate) should be combined with an effective re-vegetation of the site. Establish desirable perennial grasses and winter annuals.
  • Several biocontrol insect species have shown marked success at management of infestations, when introduced.
  • For three to four years following treatment, monitor areas for new plants from the seed bank.

Control methods and timing

March April May June July Aug Sept Oct
 

Mech

Mech

Mech

Mech

Mech

Mech

Chem

Cult

Mech

Chem

Cult

Prevention (Prev) Monitor and destroy new plants before seed production.

Mechanical (Mech) Hand pulling, digging, cutting, mowing and tilling.

Cultural (Cult) Biological control agents, livestock grazing, and revegetation practices.

Chemical (Chem) Selective herbicides based on the plant and the specific location. Check our weed fact sheets for specific control information.

Large Images

 

dalmation_toadflax_1
K. George Beck and James Sebastian, Colorado State University, Bugwood.org

Dalmatian toadflax: flowers

 

dalmation_toadflax_2
K. Mosbruger, Salt Lake County Weed Control Program

Dalmatian toadflax: foliage

 

dalmation_toadflax_3
K. Mosbruger, Salt Lake County Weed Control Program

Dalmatian toadflax: flowers

 

dalmation_toadflax_4
Steve Dewey, Utah State University, Bugwood.org

Dalmatian toadflax: infestation

 

dalmation_toadflax_5
Linda Wilson, University of Idaho, Bugwood.org

Dalmatian toadflax:: foliage growing up from old shoots

 

dalmation_toadflax_6
K. Mosbruger, Salt Lake County Weed Control Program

Dalmatian toadflax: weevil used as biocontrol agent

 

dalmation_toadflax_7
Linda Wilson, University of Idaho, Bugwood.org

Dalmatian toadflax: root system

 

dalmation_toadflax_8
Utah State University , Bugwood.org

Dalmatian toadflax: infestation

Resources

  • References

    Colorado Department of Agriculture. Dalmation toadflax biocontrol. Retrieved from https://www.colorado.gov/pacific/agconservation/dalmatian-toadflax-biocontrol

    Forest Health Technology Enterprise Team. (2005, September). Biology and biological control of dalmation and yellow toadflax [PDF file]. Retrieved from https://www.fs.fed.us/rm/pubs_other/rmrs_2005_wilson_l001.pdf View PDF

    Invasive Species Compendium. (2018, January 3). Linaria dalmatica (dalmation toadflax). Retrieved from https://www.cabi.org/isc/datasheet/30827

    King County Noxious Weed Control Program. (2017, September 29). Dalmation toadflax identification and control. Retrieved from https://www.kingcounty.gov/services/environment/animals-and-plants/noxious-weeds/weed-identification/dalmatian-toadflax.aspx

    Washington State University. (2006). Dalmation Toadflax. Retrieved from https://extension.wsu.edu/whitman/2013/11/dalmatian-toadflax/