Tyrol knapweed (Centaurea nigrescens)

Tyrol knapweed Synonyms: Centaures vochinensis, C. dubia

Common Names: vochin knapweed, alpine knapweed, wocheiner knapweed, and short-fringed knapweed

Description:

Habit: Perennial, growing from 19 inches to 5 feet tall. Stems are upright, branched and covered in hairs. Typically flowers from summer to fall.

Leaves: Basal leaves are oblanceolate to elliptic. Upper leaves are lanceolate and progressively decrease in size up the stem. Hairless or lightly hairy on the undersides; deeply lobed to irregularly cut. Terminal love is larger than others.

Stems: Upright, branched and erect. Can reach a height of 19 inches to 5 feet.

Flowers: Lavender to purple in color and occur singularly at the ends of branches. Bract (long fringes beneath the flowerhead) tips are dark brown, long and slender. Bract tips have a somewhat triangular fringe.

Fruit and seeds: Seeds are tan in color with fine hairs. Plants produce on average a few thousand seeds per plant.

Habitat: Native to Europe. Found in open grasslands, prairies, open forests, orchards, cultivated fields, field edges, and travel corridors.

Reproduction: By seed and vegetatively by root fragments.

Similar species: Other species of knapweed (Centaurea).

Monitoring and rapid response: Hand pull plants, removing the entire tap root. Mow or cut plants before flowering to prevent seed-set. Herbicide treatments are most effective when combines with other control techniques. 3% solution of triclopyr herbicide mixed with water can be applied to leaves in early spring or fall. Gall flies (Urophora affinis and Urophora quadrifasciata) are used to feed on developing seed heads.

Credits: The information provided in this factsheet was gathered from the Wisconsin Department of Natural Resources and the Washington State Noxious Weed Control Board.

Individual species images that appear with a number in a black box are courtesy of the Bugwood.org network (http://www.invasive.org).Individual photo author credits may not be included due to the small display size of the images and subsequent difficulty of reading the provided text. All other images appear courtesy of Google (http://images.google.com).


Common Name:

Tyrol knapweed

Scientific Name:

Centaurea nigrescens

Family:

Asteraceae
(Aster)

Duration:

Perennial

Habit:

Herbs

USDA Symbol:

CENI3
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