BugwoodWiki Article

spotted knapweed
Centaurea stoebe ssp. micranthos (Gugler) Hayek

Overview

Appearance
Centaurea stoebe ssp. micranthos is an herbaceous biennial or perennial plant that readily invades open areas. Its name is derived from the black margins of the flower bract tips which give the flower heads a spotted look.
Foliage
A basal rosette of deeply lobed leaves is produced the first year. Rosette leaves are deeply lobed, petiolate, and approximately 8 in. (20 cm) long. Flowering stems are 1-4 ft. (0.3-1.2 m) tall and branched. Stem leaves are alternate and may be slightly lobed or linear. Leaves become smaller and less lobed toward the apex.
Flowers
The small purple to pink flowers bloom in the early summer.
Fruit
Mature seeds are shiny black and produced in erect, slender green pods which turn pale brown when mature. The copious seeds are distributed by the wind and contaminated hay.
Ecological Threat
Centaurea stoebe ssp. micranthos invades a wide variety of habitats including pastures, open forests, prairies, meadows, old fields, and disturbed areas. It displaces native vegetation and reduces the forage potential for wildlife and livestock. It is native to Europe and western Asia. It was accidentally introduced into North America in contaminated alfalfa and clover seed in the late 1800s.

Resources

Selected Images


1459272
1459272

spotted knapweed
Centaurea stoebe ssp. micranthos
Plant(s)
Steve Dewey
5374335
5374335

spotted knapweed
Centaurea stoebe ssp. micranthos
Flower(s)
Joseph M. DiTomaso
0021034
0021034

spotted knapweed
Centaurea stoebe ssp. micranthos
Flower(s)
Norman E. Rees
5392027
5392027

spotted knapweed
Centaurea stoebe ssp. micranthos
Flower(s)
John M. Randall
1459269
1459269

spotted knapweed
Centaurea stoebe ssp. micranthos
Plant(s)
Steve Dewey
1459267
1459267

spotted knapweed
Centaurea stoebe ssp. micranthos
Plant(s)
Steve Dewey
1557011
1557011

spotted knapweed
Centaurea stoebe ssp. micranthos
Foliage
John Cardina
1551078
1551078

spotted knapweed
Centaurea stoebe ssp. micranthos
Fruit(s)
Ken Chamberlain
5391592
5391592

spotted knapweed
Centaurea stoebe ssp. micranthos
Fruit(s)
Barry Rice
2308109
2308109

spotted knapweed
Centaurea stoebe ssp. micranthos
Infestation
John M. Randall
5374334
5374334

spotted knapweed
Centaurea stoebe ssp. micranthos
Plant(s)
Joseph M. DiTomaso

Maps


EDDMapS Distribution - This map is incomplete and is based only on current site and county level reports made by experts, herbaria, and literature. For more information, visit www.eddmaps.org

EDDMapS Distribution

State Regulated List - This map identifies those states that list this species on their regulated list. For more information, visit Invasive.org

State Regulated List

Invasive Listing Sources

Taxonomic Rank

Kingdom: Plantae
Phylum: Magnoliophyta
Class: Magnoliopsida
Subclass: Asteridae
Order: Asterales
Family: Asteraceae
Genus: Centaurea

Other System Links

Plants: CESTM
GRIN: 419663
ITIS: 501347

Synonyms and Other Names

Other Common Names:
bushy knapweed

Related Scientific Names:

Centaurea biebersteinii (Gugler) Hayek(Synonym)
Centaurea maculosa auct. non Lam.(Synonym)

Categories

Category: Forbs/Herbs