Washington State Weeds

Blueweed

 Echium vulgare • Class B

Family Name: Boraginaceae (Bor-AJ-in-nee-see-ee)
Common: Forget-me-not family
Genus: Echium (ECK-ee-um)
Meaning: Greek word for viper, the nutlets resemble a viper's head
Species: vulgare (vul-GAIR-ee)
Meaning: Common
Description:

Blueweed stems are covered with short, stiff hairs, with dark flecks at the base of some hairs. Its flowering stems grow from 1 to 3 feet tall.

Leaves are lance shaped and hairy, becoming smaller and stalk-less as they grow alternately up the stem.  Leaves often have dark flecks on the undersides.

Plants bloom from June through August; seeds mature about a month after bloom.

Bright blue, funnel shaped flowers are arranged on the upper side of the stems. Buds are reddish-purple, becoming bright blue at full bloom.

Each plant can produce up to 2,800 seeds that can remain viable in the soil for several years.

 


 Why Is it a Noxious Weed? It invades pasturelands, outcompletes desirable vegetation, and is unpalatable to livestock. It is believed to contain several pyrrolizidine alkaloids, which accumulate in the liver and cause liver damage. Skin contact with the bristly hairs of the blueweed may cause dermatitis resulting in inflammation and itching.

Where Does it Grow?

Blueweed does well in a variety of soil types, including poor soils, but does not tolerate shade. It

grows on rangeland, rocky pastures, roadsides, waterways, and vacant lots. It is considered

unpalatable to livestock because of its coarse hairs and toxic alkaloids.


Control Options:
  • The most effective control of Blueweed is prevention. Above all, prevent plants from going to seed.
  • Selective, translocated herbicides such as Picloram and 2, 4 D are two herbicides that can be effective on blueweed.
  • Spot spraying with an herbicide containing the active ingredient glyphosate can also be effective. Glyphosate is non- selective however and will injure any plants that it comes in contact with. Spot applications should be applied at bud stage, prior to blooming.
  • When using herbicides, carefully read and follow all label instructions and obey all label precautions. (Note: pesticide product registration is renewed annually and product names and formulations may vary from year to year.)
  • To minimize any harmful impact on bees and other pollinators, timing is important.  Ideally, treat plants before blooming.  If treatment after blooming is necessary, do control work early in the morning, or in the evening when bees are less active.

More Information:

For more information on this noxious weed  Download our Flyer or visit Washington State Noxious Weed Control Board Here. Photo by Leo Michels and Rebecca Shoemaker.

 


More Pictures:  

blueweed flowering blueweed, noxious weed in pierce county, wa