Dalmatian toadflax

Linaria dalmatica ssp. dalmatica

   

Family: Scrophulariaceae

Other common names: Balkan toadflax, broadleaf toadflax

Weed Class: B

Year Listed: 1988

Native to: The Dalmatian coast of the former Yugoslavia to Romania, Bulgaria, Albania, Greece, Crete, Turkey, Azerbaijan, Syria, Iran, and Iraq.

Toxic: not known to be

Other Legal Listings: WA Quarantine list, WAC 16-750

additional photos

 

   

Why is it a noxious weed?

Mature plants are strongly competitive, especially with shallow-rooted perennials and winter annuals. Dalmatian toadflax causes negative impacts in pastures, rangelands, and natural areas, where it outcompetes natives or other desirable species.

How would I identify it?

General Description: Dalmatian toadflax is a short-lived, perennial herb, 2.6 feet to 5 feet tall with light green leaves and yellow snapdragon-like flowers.

Flower Description: Flowers are bright yellow, tinged with orange and resemble snapdragon flowers. The petals have 2 lips. The upper lip is 2 lobed and the lower lip is 3 lobed. Individual flowers occur on long racemes.

Leaf Description: Leaves are heart-shaped, light green and waxy. They are alternately arranged and lack petioles (leave stems) and appear to clasp the stem.

Stem Description: Stems are stout and upright, branching toward the top.

Fruit/Seed Description: Capsules that are 0.28 to 0.31 inches long, egg to cylinder shaped with many small seeds.

May be confused with: Yellow toadflax, Linaria vulgaris, is very similar in appearance. If you need help with plant identification, please contact your county noxious weed coordinator.

How does it reproduce?

Dalmatian toadflax spreads by horizontal or creeping rootstocks as well as by seed. A mature plant can produce up to 500,000 seeds.
 

Where does it grow?

Dalmatian toadflax can be found on roadsides, in pastures, rangeland and waste areas. Please click here to see a county level distribution map of Dalmatian toadflax in Washington.
 

How do I control it?

Mechanical Control

Hand-pulling and digging can be effective on small patches and can result in eradication if done consistently for 5-6 years.

Cultural Control

Intensive clean cultivation can effectively control Dalmatian toadflax. Cultivation methods must continue for at least two years, with eight to ten cultivations in the first year and four to five in the next year.

Biological Control

The toadflax stem weevil, Mecinus janthinus is a biocontrol agent used in Washington state to control Dalmatian toadflax. Mecinus janthinus's larvae feed (or mine) within the plant's stems, which inhibits the transportation of nutrients, resulting in premature wilting of shoots and reduced flower production. Adults also feed on leaves and stems and can suppress plant growth. For more information about the biological control of Dalmatian toadflax, please visit WSU Extension Integrated Weed Control Project.

Herbicide Control

Please refer to the PNW Weed Management Handbook, or contact your county noxious weed coordinator.


 

For more information

 
Report on Dalmatian toadflax from the book "Weed Control in Natural Areas in the Western United States"
See our Written Findings for more information about Dalmatian toadflax (Linaria dalmatica ssp. dalmatica).

Additional Photos


 
 

 


Dalmatian toadflax infestion

 


Dalmatian toadflax flower

 


flower detail

 


infestation

 


infestation

 


close up of leaf damage

 


old stem on left, blooming plant on right

 


infestation

 


young stem tip

 


shape and underside of young leaves

 


spring growth

 


plant habit

 


blooming plant habit

    

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