Family: Scrophulariaceae (figwort family)
Life cycle: Perennial
Roots: Deep, extensive root system
Leaves are cordate (heart-shaped), very waxy and clasp the stem
Flowers are snap-dragon form and each plant can produce 300,000 to 500,000 seeds per/year
Note: Yellow toadflax (Linaria vulgaris) has similar flowers and root structure but leaves are more narrow and lanceolate shape. Growth patterns also differ. Effective treatments are similar.
Effective control methods:
Mechanical: Hand pulling very small patches has been known to work. Start pulling early in the season and make sure to get as much of the root as possible. This method could take many years.
Chemical – Herbicides such as Tordon 22K (Picloram) and Telar (Chlorsulfuron) work very well with a surfactant to penetrate the waxy cuticle. Treatment time is best in the beginning stages of flower but this weed can be treated with herbicides that have a high residual all year.
Bio-Controls: Mecinus janthinus is a stem boring weevil that works very well to control Dalmatian toadflax infestations. Contact Weedbusters at www.weedbustersbiocontrol.com