1. Skip to Menu
  2. Skip to Content
  3. Skip to Footer

Dalmatian Toadflax

dalmatian toadflax

Linaria dalmatica • Class B

Family Name: Scrophulariaceae (skrof-yoo-larr-ee-AY-see-ee)
Common: Snapdragon family
Genus: Linaria (lin-AR-ee-uh)  
Meaning: Flax-like
Species: dalmatica (dal-MAT-ih-kuh)
Meaning: Of or from Dalmatia, Croatia on the Adriatic Sea
Description:

Dalmatian toadflax is an erect perennial herb standing from 2.5 to 5 feet tall. It‘s waxy, light green, alternate leaves are heart shaped and clasp the woody branching stems. It blooms from May to August and flowers are bright yellow, tinged with orange and closely resembles the snapdragon. The petals have 2 lips, the upper petals have 2 lobes and the lower is 3 lobed. The root system may be as deep as six feet and may spread laterally as much as ten feet. 


 Why Is it a Noxious Plant?

Dalmatian toadflax outcompetes native plants and other desirable species and contains a poisonous glucoside which is toxic to livestock. 


Where Does it Grow?

The plant grows along roadsides, in pastures, idle land, and rangeland, particularly in sites with coarse-textured soils. Its extensive root system allows the plant to survive in adverse soils and climatic conditions. 


Facts:

D.T. seedlings are poor competitors for soil moisture against established plants, but once established they become extremely competitive and substantially affect the surrounding vegetation. A mature plant can produce up to 500,000 seeds a year which are primarily dispersed by wind. 


Control Options:

Preventing the establishment of populations of Dalmatian toadflax is the most time and cost effective way of controlling this species.  

  • Plants are easiest to control in the seedling stage and when found should be removed immediately. 
  • Pulling small infestations before they become established can be an effective control method, especially if growing in sandy or moist soil. 
  • The toadflax stem weevil, Mecinus janthinus is a biocontrol agent used in Washington State to control Dalmatian toadflax. For information about the biological control of this or any other noxious weed, see the WSU Extension Integrated Weed Control Project ..  
  • Spot spraying with an herbicide containing the active ingredient Glyphosate (Roundup Pro, Glyfos, etc.) may be used effectively while the plant is actively growing, repeat as needed. Be aware, Glyphosate is non-selective and will injure any plants that it comes in contact with, including grass. 
  • 2, 4 D plus Dicamba (Weedmaster, Crossbow, etc) is also effective. Spray the plant and an area 10 feet in diameter around it before the bloom stage and repeat as needed. 
  • When using herbicides, read and follow all label instructions and obey all label precautions. (Note: pesticide product registration is renewed annually and product names and formulations may vary from year to year.) 

More Information:

 Download our Flyer or visit Washington State Noxious Weed Control Board Here.  Photos by Rebecca Shoemaker, Pierce County Noxious Weed Control Board.

 


More Pictures:

dalmation Toadflax

dalmation toadsflax

 

 

Washington State Weeds