Weed Control
Home ⟩ Noxious Weeds ⟩ Orange and Yellow Flowering Plants ⟩ Yellow Toadflax
Yellow Toadflax
Information | Images
Linaria vulgaris
Creeping perennial
Identification and management tips
- Yellow toadflax flowers are bright yellow and resemble snapdragons.
- The leaves of yellow toadflax are easily distinguished from dalmation toadflax. Yellow toadflax leaves are narrow, lance-shaped, and pointed at both ends. The leaves of dalmation toadflax are shorter, wider, and broad-based.
- Yellow toadflax aggressively forms colonies through adventitious buds from creeping root systems.
- Flowering occurs from May through August and seeds mature from July through October.
- A mature plant can produce up to 30,000 seeds annually. These seeds can remain dormant for up to ten years.
- The key to controlling yellow toadflax is to limit vegetative spread of established colonies (by cutting, pulling, or spraying seed stalks prior to seed set, or by using insects to destroy flowers, seeds, or damage plants).
- Hand pulling toadflax before seed set each year can be an effective control method especially in coarse-textured soils where large portions of the roots can be pulled. However, this method must be repeated as long as there are viable seeds in the soil (up to 10 years).
- Yellow toadflax is difficult to control with herbicides, and the effectiveness is highly variable.
- Herbicides should be applied during flowering when carbohydrate reserves in the root of the plants are at their lowest. Picloram or dicamba at 1 lb. ai/acre, or glyphosate at 1.5 lb. ai/acre, will kill yellow toadflax plants in some situations.
Most effective control methods and timing
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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.
Links
Photo credits
Left to right:
- Michael Shephard, USDA Forest Service, Bugwood.org
- John Cardina, The Ohio State University, Bugwood.org
- L.L. Berry, Bugwood.org