Dalmatian Toadflax

• List B – to be eliminated or suppressed depending on the infestation
• Native to the Mediterrean area introduces as ornamental plant
• Tall (3ft) plant that reproduces by seed and creeping underground roots
• One plant can produce 500,000 seeds but does not spread far
• Control best accomplished by early detection and eradication or multiple management strategies

Diffuse Knapweed

• List B – to be eliminated or suppressed depending on the infestation
• Native to the Mediterranean area
• Tends to invade disturbed or overgrazed areas and roadsides
• One plant can produce 18,000 seeds that may remain dormant for years but still be viable
• Also known to outcompete native plants by releasing a chemical in the soil that suppresses other plant growth

Learn more about Diffuse Knapweed

Leafy Spurge

• List B – to be eliminated or suppressed depending on the infestation
• Native to central and southern Europe
• Long-living creeping perennial that spreads by seed but also has extensive root system that makes control difficult
• A management scheme that combines control methods over four to five years is recommended

Musk Thistle

• List B – to be eliminated or suppressed depending on the infestation
• Spreads only by seed but one plant can produce up to 20,000 seeds
• Prefers open degraded habitat and pastures
• Can grow up to 6 feet tall

Myrtle Spurge

• List A – must be eradicated on all property
• also called "donkey tail" or "creeping spurge"
• drought-tolerant perennial native to Eurasia, first introduced to North America as an ornamental
• considered a noxious weed because it is aggressive and proliferates easily, outcompetes native plants, and has toxic milky sap

Replacements for Myrtle Spurge

• Colorado Four o'clock (Mirabilis multiflora)
• Sulphur-flower Buckwheat (Eriogonum umbellatum)
• Kinnikinnick (Arctostaphylos uva-ursi)
• Creeping Barberry (Mahonia repens)
• Four-nerve Daisy (Tetraneuris acaulis)
• Tufted Evening Primrose (Oenothera caespitosa)