Dalmatian Toadflax

dalmatian toadflax flower
dalmatian toadflax root
dalmatian toadflax plant
dalmatian toadflax leaves

Dalmation Toadflax

Linaria dalmatica

Information Sheet (PDF)


Colorado List B - Control required in Jefferson County


General

  • Family: Plantaginaceae (Plantain)
  • Grows from sea level to 9,200 feet
  • Has been used as an ornamental but no longer available in Colorado
  • Herbaceous perennial
  • Individual patches can live for 13 or more years
  • Toadflax can significantly reduce crop yields and stress native communities


Common Names

  • Wild snapdragon


Habitat

  • Found in pastures, rangelands, roadsides, gravel pits and grasslands
  • Prefers open, sunny locations
  • Tolerant to low temperatures and coarse soils


Plant


Vegetation

  • 1 to 3 inches long, 3/8 to 3/4 inch wide and waxy
  • Leaves are heart-shaped and clasp the stem
  • Mature plants up to 3 feet tall
  • Produces 1 to 25 floral stems
  • Stems are woody at the base
  • Top growth dies back in fall, prostrate stems form in the fall and during winter


Roots

  • Lateral roots are found 2 to 8 inches deep, can extend horizontally 10 or more feet
  • New plants can develop from root buds 2 to 3 weeks after germination and from root fragments as small as 1/4 inch long
  • Taproots can reach 6 plus feet deep


Flower

  • Color: yellow
  • Season: spring to fall
  • Size: 3/4 to 1 1/2 inches long
  • Typically has a spur as long as the flower


Seed

  • Each plant can produce up to 500,000 seeds
  • Remains viable up to 10 years
  • Seed capsules begin opening in July
  • Seed matures from July through September


Seedling

  • Most emerge in April
  • Some fall germination possible under optimum conditions


Reproduction

  • Seed and vegetative means


Control


Biological

  • Calophasia lunula, a defoliating moth (L)
  • Brachypterolus pulicarius, Toadflax flower-feeding beetle (A)


Chemical


Cultural

  • Fertilization to promote grass cover
  • Prevention - maintain health of site
  • Removal of prostrate stems in spring and fall reduces floral stems
  • Re-vegetation of highly disturbed sites


Mechanical

  • Burning - Not recommended; deep roots protect the plant; areas disturbed by fire  are susceptible to re-invasion due to lack of competition from desirable  plants
  • Grazing - Does not control; intensive grazing contributes to ideal habitat  conditions, helping dalmatian toadflax spread; may be toxic to  livestock 
  • Mowing- Not recommended


Use all chemicals according to the manufacturer's label. No specific recommendation or endorsement is made or implied by listing methods or products.

Treatment Timeline


JanFebMarAprMayJuneJulyAugSeptOctNovDec
Control











RemovalRemoval not recommended - plants regrow from root fragments
Cut + Herbicide


cutcutcutcutcutherbherb

Herbicide











Biological











Growth











Vegetative











Flowering











Seed