Noxious and Non-Native Weeds in Utah County

Tamarix | salt cedar

read about the history of this invasive species and why we need to be concerned about it's presence in Utah County. more

Weed Alert!

Viper's bugloss was recently rediscovered and confirmed in Wyoming. The plant causes reason for concern because of contact dermatitis for humans, potential toxicity to livestock due to pyrrolizodine alkaloids, a host for several crop pathogens, and a potential increaser on grazed rangelands due to its unpalatable nature (this concern probably precludes worries of toxicity for cattle ranchers; however, sheep and horses may be a different story).

The plant is a biennial and may sometimes occur as a short lived monocarpic perennial. First year rosette leaves may be from 2-25 cm long inches long, 0.5-3 cm wide, entire, oblanceolate, single-nerved with a short petiole, and covered with stiff hairs. Second year plants typically bolt and produce 1-20 flowering stems and are 30-100 cm tall. The stems are grey green and covered with two types of hair: stout spreading hairs with a pustulate base and an under layer of smaller fine hairs. The stout spreading hairs arise from small black speckles on the stem (tubercles). Stem leaves are alternate, sessile, and linear to lanceolate becoming smaller up the stems. The inflorescence is a panicle of several short helicoid cymes of bright blue to purple flowers. Flowering occurs during the summer months of July and August.

NEW

• The Homeowners Guide to Cheatgrass is a fantastic resource for home owners who are struggling with this invasive plant species.
• Download the new Common Backyard Weeds & Their Control - an inclusive publication that provides homeowners with valuable information on how to manage invasive weeds on their property.
• Download and view the Intermountain Regions Master Noxious Weed list (.pdf) that details every listed Noxious weed in the Intermountain Region.

Knapweeds

Knapweeds belong to an aggressive group of weeds that have been invading western deserts. There are five very troublesome versions of knapweed: diffuse knapweed, squarrose knapweed, spotted knapweed, russian knapweed and yellow starthiste.

Knapweeds originated in Eurasia and, mixed up with imported alphalpha, found their way to the United States. Since their arrivel, they have spread throughout most of the northwestern states and are serously endangering the quality of forage available for lifestock and wildlife. Read more about the different species of knapweeds: