Noxious Weed Quick Facts
- Yellow toadflax “snapdragon” flowers have a long spur and usually an orange throat.
- This plant typically blooms in June to September.
- Toadflax forms big colonies. Each plant can drop 15,000–30,000 seeds that can remain viable in soil for up to a decade.
- Pull or dig small patches repeatedly and bag any flowers/seeds to avoid re-seed the area (it’s hard to control overall).
Yellow toadflax, sometimes called “butter-and-eggs,” is often one of the first plants to return after forest fire.
Large colonies can be found in disturbed areas, meadows, pastures, and rights-of-way.
Yellow flowers are snapdragon-shaped with distinctive long spurs and often have an orange throat. Flowers grow in groups at the end of stems and can usually be found from June through September.
Multiple stems grow from the crown. Plants can grow up to two feet tall. Leaves are narrow, waxy, and attach directly to stems.
Each plant can produce 15,000 to 30,000 seeds that will last for about 10 years in the soil.
Pulling or digging is effective on small populations if repeated multiple times a year. Any flowers and/or seeds should be bagged and disposed of.
Contact Gilpin County Extension for specific herbicide applications.
Important notes:
- This highly invasive plant is difficult to control
- Often found in disturbed and degraded areas
- List B Noxious Weed in Colorado
- State law: Toadflax must be eradicated or contained in Gilpin County.
Native look-alike: Western or White Virgin’s Bower Clematis
State law: Toadflax must be eradicated or contained in Gilpin County.
The a native plant, Golden Banner (Thermopsis divaricarpa) is often confused for toadflax. Observe leaves to distinguish these plants more easily. The leaves of yellow toadflax are linear. The leaves of Golden Banner have three leaflets (like a clover).
 | Golden banner (a good/native plant) has leaflets like a clover. |
 | Yellow toadflax (a bad/noxious weed) has linear leaves. |