Scientific Name: Echium
Common Names: blueweed,
History: Blueweed is part of the Boraginaceae or
borage family, originated from southern Europe, and is a
biennial or short lived perennial. It is believed that
blueweed was first introduced to the U.S. as an ornamental and
it can now be found throughout the country.
Roots: Blueweed has a long tap root with smaller root
hairs that extend off of it. The
tap root is typically black with a reddish cast and can be
anywhere from 30.5 to 81cm (12 to 32 in.) in length. Blueweed
can also regenerate from root fragments.
Stems and Leaves: The leaves of a blueweed plant
start at the bottom in a ring called a basal rosette. These
leaves are oblong and smooth edged growing from six to 22.5 cm
(two to ten inches) in length. The stems are tall and straight
growing up to 36 inches in height and each plant can have
multiple stems. Each stem is covered in small hairs that
have a purple or reddish base giving the stems a spotted
appearance. The leaves on the stem are also oblong and they
alternate getting smaller towards the top.
Flowers: Blueweed has bright blue funnel or bell shaped
flowers that range from one to two centimeters in size and can
vary slightly in color. Each flower has five petals or lobes,
and usually five stamens, which are pink to red in color and one
is typically shorter than the rest. To flower, the plant needs
to be exposed to colder temperatures before its first bloom of
the season. Blueweed produces flowers from June to July and then
again from August to October.
Seeds: The seeds are brownish gray and have a rounded
pyramid shape. They are less than .10 inches in diameter and
have a rough hard exterior that sticks well to clothing and
animals. Each plant can produce 500 to 2000 seeds and they can
remain viable in the soil for up to 36 months. Seeds are the
main method of reproduction.
Environments Favorable For Infestation: Over
grazed pastures, range land, and other disturbed areas are prime
for the invasion of blueweed. Typically, blueweed will infest
areas where there is no other, or very little, existing
vegetation and where the soil is drier and sandier with little
Economic and Environmental Impacts: Blueweed is toxic to
cattle and horses in large amounts and is known to cause liver
failure. It is also a host for plant diseases such as
alfalfa mosaic virus, tobacco mosaic virus, and it is a
secondary host for wheat rust. The stems and leaves are rough
due to the hairs covering them and can cause skin irritations in
Range: Blueweed infests 43 of the lower 48 states and is
a listed noxious weed in Montana and Washington. As of 2015,
infested Montana counties include: Cascade, Flathead, Lake,
Lewis and Clark, Lincoln, Madison, Mineral, Missoula, Powell,
Ravalli, Sanders, Sweet Grass, and Treasure.
Prevention: Brush out coats of animals
and wash the undercarriages of vehicles to prevent the
accidental spread of this weed by transportation of its
Mechanical: Digging and hand pulling are recommended
for small patches and continuous mowing and clipping can be
used for larger infestations.
Cultural: Proper management of lawns and pastures
such as keeping native and desired plants healthy and
soil fertile. Re-vegetation of areas previously infested can
also slow the spread of the weed as it does not do well in
shaded or healthy areas. Using goats and sheep to graze is
also an alternative control.
Biological: There are currently no insects approved
to be used as a bio-control agent in the U.S.
Chemical: A mixture of Escort and Telar used on
the basal rosettes early in the spring was found to be 100%
effective in controlling blueweed up to a year. 2,4-D LVE
was also found to be effective in pastures along with
crossbow (2,4-D and Triclopyr).
Other: Prescribed burning is not effective
because the weed doesn't burn well until it has been dried
out for several days.
1."Biology, Ecology, and Management of Blueweed." Web. 7
Aug. 2015. <http://store.msuextension.org/publications/AgandNaturalResources/EB0195.pdf>.
2."Blueweed (Echium Vulgare)." Blueweed. Web. 7 Aug.
3."Montana Weed Control Association." Montana Weed Control
Association. Web. 7 Aug. 2015. <http://mtweed.org/weeds/blueweed/>.
4."TexasInvasives.org - Home." Texas Invasives. Web. 7
Aug. 2015. <http://www.texasinvasives.org/plant_database/detail.php?symbol=ECVU>.
8/07/15 by: Alycia
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