Yellow Toadflax

Yellow Toadflax

Linaria vulgaris
linaria_vulgaris_yellow_toadflax_flowers_ssisc

Status in Squamish:

STRATEGIC-CONTROL

Status in Whistler:

STRATEGIC-CONTROL

Status in Pemberton:

STRATEGIC-CONTROL
Vectors of Spread:
Synonyms

Common Toadflax, Butter and Eggs, Wild Snapdragon

ID Characteristics

General: Yellow Toadflax is a perennial forb.

Flowers: Bright yellow “snapdragon-like” flowers. Yellow Toadflax flowers are arranged in a raceme at the ends of each branch. The yellow flowers have orange colouring on the throat.

Stem: Are erect, hairless, and unbranched. The stems can grow 0.15 – 1.0 m tall. Mature plants can have as many as 25 stems.

Leaves: The soft, lance-shaped, and pale green leaves are attached directly to the stem. The leaves are alternate and can be up to 10 cm long.

Fruit: Winged, disk-shaped, 5-10 mm tall, and dark brown to black.

Roots: Taproots with lateral creeping roots.

Similar Species

Invasive:

Dalmation Toadflax (Linaria dalmatica)

Dalmatian Toadflax (Linaria dalmatica) has broad, heart-shaped leaves and a woody stem.

 

 

 

 

Leafy Spurge (Euphorbia esula)

Leafy Spurge (Euphorbia esula) stems exude a milky latex when broken.

Report

Please report any sighting of Yellow Toadflax by clicking here.

Habitat and Origin

Yellow Toadflax was introduced from Europe and Asia in the mid-1800s as an ornamental garden plant. It was also used to make dye and folk remedies.

Yellow Toadflax can be found in well-drained, open, low-elevation forests and grasslands. It is most commonly found in gravelly soil on roadsides, railroads, pastures, cultivated fields, and clear-cuts.

Current Distribution

Propagation & Vectors of Spread

Yellow Toadflax reproduces through seed and vegetatively, via root segments. A mature plant can produce up to 30, 000 seeds annually and they can remain viable in the soil for up to ten years. Root fragments as short as 1 cm can grow into a full plant the following year.

Yellow Toadflax can spread locally via vegetative reproduction through the root systems, but long-distance dispersal occurs through the transport of seeds. The wind primarily carries seeds, but water, animals, and humans (via clothing, equipment, and vehicles) may also spread the seeds.

Ecological, Economic, & Health Impacts

Ecological: 

  • Toxic to wildlife.
  • Competes with native plants.
  • Reduces biodiversity.

Economic:

  • Reduces foraging area for livestock.
What Can I Do?

Yellow Toadflax is currently found throughout the Sea to Sky Corridor, so the best approach to controlling its spread is by PREVENTION.

 

Learn to identify Yellow Toadflax: use the images presented in this profile page to learn how to identify Yellow Toadflax.

What to do if you spot it: You can report any Yellow Toadflax sighting by clicking here.

 

DO:

  • Regularly monitor properties for weed infestations.
  • Ensure soil and gravel are uncontaminated before transport.
  • Check wildflower mixes to ensure that they do not contain Yellow Toadflax.
  • Ensure that plants are disposed of in a garbage bag if found in floral arrangements to prevent seeds from spreading.

 

DO NOT:

  • Unload, park or store equipment or vehicles in infested areas; remove plant material from any equipment, vehicles, or clothing used in such areas and wash equipment and vehicles at designated cleaning sites before leaving infested areas.
  • Plant Yellow Toadflax in a garden, no matter how well-contained its enclosure may seem.
  • Move soil that has been contaminated with Yellow Toadflax.
  • Compost Yellow Toadflax.

 

Control

Mechanical

Hand-pulling is effective, especially in coarse-textured soils where roots can be removed easily. Cutting or mowing is not recommended because it does not kill the plant. Any plant material that is removed should be placed in a plastic bag and disposed of at the landfill.

Chemical

Difficult to manage with herbicides. Herbicides should be applied during flowering when carbohydrate reserves in the root are at their lowest. Dicamba and picloram (with or without 2,4-D) have been effective in some situations; however, picloram is not suitable for wet, coastal soils. We recommend that any herbicide application is carried out by a person holding a valid BC Pesticide Applicator Certificate. Before selecting and applying herbicides, you must review and follow herbicide labels and application rates; municipal, regional, provincial, and federal laws and regulations; species-specific treatment recommendations, and site-specific goals and objectives.

Biological

Five species occur in BC that could be used for Yellow Toadflax biocontrol: Brachypterolus pulicarius (beetle), Calophasia lunula (moth), Eteobalea intermediella (moth), Gymnaetron antirrhini (weevil), and Mecinus janthinus (beetle).

References