Invasive Species: Linaria vulgaris, Yellow Toadflax
Yellow toadflax is an invasive perennial herb that can reach 3.3 ft. (1 m) tall. Leaves are nearly sessile, drooping, linear, and 1 to 2 in. (2.5 to 5 cm) long. Leaves can sometimes be sparsely covered by long hairs. Flowering occurs from May to September, when yellow/white, snapdragon-like flowers develop. Flowers, including the spur, are 0.6 to 1.2 in. (1.5 to 3 cm) long and occur in racemes at the apex of the stems. Fruits are capsules that are 0.4 to 0.5 in. (9 to 12 mm) long. Each capsule contains small, flat seeds with a papery wing. Yellow toadflax is native to Europe and was introduced into North America, as an ornamental, in the mid 1600s. Plants occur in fields, pastures, roadsides, undisturbed prairies, and rangelands.
What are invasive species and why should we be concerned about them?
Taxonomy: Scientific and Common Names for This Species
Scrophulariales > Scrophulariaceae > Linaria vulgaris P. Mill.
Synonym(s): butter and eggs, Jacob’s ladder, wild snapdragon
Linaria vulgaris – USDA PLANTS Profile
Distribution Maps
Yellow toadflax – The reported distribution of this invasive species across the United States (Source: Invasive Plant Atlas of the United States)
Up-to-the-minute distribution maps and why they are important
Reporting This Invasive Species
What is the best way and place to report the occurrence of an invasive species?
How to report an invasive species sighting to EDDMapS – Early Detection & Distribution Mapping System
EDDMapS – Report an invasive species to EDDMapS.
Cooperative Extension Offices – Find your local Cooperative Extension office on this map provided by USDA.
How to Identify
This invasive species can be identified by looking for the characteristics described in the paragraphs that follow.
Plant
Yellow toadflax is a perennial herb that can reach 3.3 ft. (1 m) tall.
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| Michael Shephard, USDA Forest service, bugwood.org | William M. Ciesla, Forest Health Management International, bugwood.org |
Foliage
Leaves are nearly sessile, drooping, linear, and 1 to 2 in. (2.5 to 5 cm) long. Leaves can sometimes be sparsely covered by long hairs.
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| John Cardina, Ohio State University, bugwood.org | Bonnie Million, National Park Service, bugwood.org |
Flower
Flowering occurs from May to September, when yellow/white, snapdragon-like flowers develop. Flowers, including the spur, are 0.6 to 1.2 in. (1.5 to 3 cm) long and occur in racemes at the apex of the stems.
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| Caleb Slemmons, University of Maine, bugwood.org | Steve Dewey, Utah State University, bugwood.org |
Fruit
Fruits are capsules that are 0.4 to 0.5 in. (9 to 12 mm) long. Each capsule contains small, flat seeds with a papery wing.
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| Steve Hurst, USDA NRCS PLANTS Database, bugwood.org | Steve Dewey, Utah State University, bugwood.org |
Native Species That Can Resemble Yellow Toadflax
– Images at invasive.org
| bugwood.org | bugwood.org |
– Images at invasive.org
| bugwood.org | bugwood.org |
Additional Images for Yellow Toadflax
Yellow toadflax – Images at Invasive.org
Additional Information, Biology, Control and Management Resources
Control and management recommendations vary according to individual circumstances. Location, habitat, weather, and a variety of other conditions are factors that help determine the best treatment choice. To find the safest and most effective treatment for your situation, consult your state’s land-grant institution. If you will use chemicals as part of the control process, always refer to the product label.
United States Land-Grant University System – Find your land-grant university’s college of agriculture, Cooperative Extension office, or other related partner on this map provided by USDA.
Element Stewardship Abstract – The Nature Conservancy
Global Invasive Species Database – Invasive Species Specialist Group (ISSG)
Plant profiles – California Invasive Plant Council
Technical Note−Invasive Species – USDA, NRCS
Weeds – Tahoeinvasiveweeds.org
Fact Sheets – University of Nevada Cooperative Extension
Stop the Spread – North Dakota State University & USDA
Weed-Factsheet – New Mexico State University
Alaska Natural Heritage Program – University of Alaska Anchorage
Fire Effects Information System – USDA Forest Service