Synonym(s): common viper's bugloss
Family: Boraginaceae (borage family)
Duration and Habit: biennial or short-lived perennial Herb
Blueweed initially forms as a basal rosette with simple, entire, and oblanceolate leaves. Leaves are 2.5 to 10 inches in length, and 0.5 and 3 inches in width. Mature plants have branching flower stems that can reach up to 3 feet in height. Stem leaves are alternately arranged, and stems and leaves are covered with hairs that give the stem a spotted appearance. Blueweed has an extensive root system, with a long tap root (12 - 32 inches) and smaller fibrous roots.
The inflorescence is a panicle with short helicoid cymes known as "scorpions tail". There are up to 50 cymes per stem, that can bear up to 20 flowers. Flowers are funnel-shaped, five-lobed, and typically bright blue (may also be purple, pink, or white). A good feature for identification is that blueweed has five pink or red stamens, one of which is noticeably shorter.
Seeds (nutlets) are brown to gray, pyramid-shaped, and very small (<0.1 inch long). Plants produce from 500 to 2,000 seeds per plant.
Ecological Threat: Blueweed reduces forage production and wildlife habitat. Livestock avoid blueweed because the stiff hairs on the stems and leaves make it unpalatable. Blueweed also has high concentrations of pyrrolizidine alkaloids in the hairs, and when ingested the accumulated alkaloids can cause liver disease.
These hairs also cause dermatitis in humans.
Blueweed is an alternate host to several crop-damaging pathogens, including wheat rust, mosaic virus, tobacco mosaic virus, and cabbage black ring spot.
Biology & Spread: Blueweed is a monocarpic perennial (i.e., flowers once then dies). This usually takes two years, but can take up to five. This life-cycle pattern leads to cyclical infestation patterns.
Blueweed emerges in the spring and rosettes develop through the winter. Rosettes must go through a cold vernalization period and reach a certain size prior to flowering. Flowering typically begins in early June and extends through September (may begin as early as March in warmer climates). It is pollinated by insects and ruby-throated hummingbirds.
Blueweed seed is considered highly viable (90%) and can remain dormant in the soil for three years if buried. Seeds mature approximately one month after flowers bloom and dispersal begins one month after maturity. Plants produce 500 to 2,000 seeds per plant, and dispersal peaks in September.
History: Blueweed has been planted as an ornamental. It also has the fatty acid composition of the seed oil and is grown an oilseed crop. Similar to evening primrose oil, it contains significant amounts of gamma linolenic acid (GLA). It also contains the rarer stearidonic acid (SdA).
U.S. Habitat: Blueweed is adapted to temperate climates having cool wet winters and warm summers. It favors coarse sandy soils of limestone or dolomite parent material, but can also be found in acidic soils and granitic parent material. It can grow well in poor soils, disturbed areas, and is typically is found in wastelands, along roadsides, near watercourses, and in overgrazed pastures. It does not grow well under dense vegetation.
U.S. Nativity: Introduced to U.S.
Native Origin: Native to Europe, including Britain. Blueweed range extends from Scandinavia south and east to Spain, the Urals and W. Asia.
USA AK, AR, CO, CT, DC, DE, GA, IA, ID, IL, IN, KS, KY, LA, MA, MD, ME, MI, MN, MO, MT, NC, NE, NH, NJ, NM, NY, OH, OK, OR, PA, RI, SC, SD, TN, TX, UT, VA, VT, WA, WI, WV, WY)
CAN AB, BC, MB, NB, NF, NS, ON, PE, QC, SK
Distribution: Blueweed is found throughout the U.S., and is listed as a noxious invasive in Washington and Montana.
USE PESTICIDES WISELY: ALWAYS READ THE ENTIRE PESTICIDE
LABEL CAREFULLY, FOLLOW ALL MIXING AND APPLICATION INSTRUCTIONS AND WEAR
ALL RECOMMENDED PERSONAL PROTECTIVE GEAR AND CLOTHING. CONTACT YOUR STATE
DEPARTMENT OF AGRICULTURE FOR ANY ADDITIONAL PESTICIDE USE REQUIREMENTS,
RESTRICTIONS OR RECOMMENDATIONS. MENTION OF PESTICIDE PRODUCTS
ON THIS WEB SITE DOES NOT CONSTITUTE ENDORSEMENT OF ANY MATERIAL.
Blueweed is not shade tolerant. Revegetation of disturbed area will prevent infestations.
Hand pulling can help to remove small infestations. The root system must be entirely removed because regeneration from roots can occur.
Mowing can temporarily remove large populations, though re-sprouting will likely occur.
There are no approved biological control methods for managing Blueweed.
The USDA NRCS Montana State Office found that:
"Herbicide trials on a rangeland site in Ravalli County, Montana, showed metsulfuron (1 ounce/acre product-Escort and others), chlorsulfuron (1 ounce/acre product-Telar and others), or their combination (0.5 + 0.5 ounce/acre) applied to rosettes in the spring or fall provided nearly 100 percent control of blueweed one year after treatment. Pasture formulations containing 2,4-D at 1-2 quarts/acre have been used successfully on blueweed in the rosette stage during active growth. Multiple applications may be required to ensure complete control of this species. Blueweed is listed on the Crossbow® label (2,4-D + triclopyr) for control using a 1 percent mixture or 1 quart/acre applied during active growth. Always consult product labels and read them carefully".
USDA-NRCS. 2010. Plant Guide: Blueweed. Usda, NRCS, Montana State Office, Bozeman, Montana.
MissouriPlants.com Found at: http://www.missouriplants.com/Bluealt/Echium_vulgare_page.html
Plants for a Future. Found at: http://www.pfaf.org/user/Plant.aspx?LatinName=Echium+vulgare
Google Search: Echium vulgare
Google Images: Echium vulgare
NatureServe Explorer: Echium vulgare
USDA Plants: Echium vulgare
Invasive Plant Atlas of the United States: Echium vulgare
Bugwood Network Images: Echium vulgare