Go to Midwest Weeds and Wildflowers Home Page

Black Knapweed

Centaurea nigra L.

Asteraceae (Sunflower Family)

No Photos Yet

Centaurea nigra L., Black Knapweed: (Bayer Code:  CENNI; US Code CENI2)

·         Simple perennial plant with stout rootstock native to Europe and found escaped from cultivation in northeastern and northwestern U.S.

·         Leaves are usually oval, with pointed tips and occasionally with shallow teeth or lobes, but usually with smooth margins, and leaves are pubescent

·         Stems are generally unbranched, and head inflorescences are at the tip of these stems

·         Heads have pinkish-purple ray flowers of equal length, and bracts tipped with dark section that has comb-like spines along its edge, and this section of the bract bends slightly outward from the head

·         Not a problem yet in Missouri

·         Similar Brown Knapweed (Centaurea jacea) has brown, papery edges to the bracts underneath the head inflorescence

·         Similar Greater Knapweed (Centaurea scabiosa) has pinnately-lobed leaves and tiny, dark teeth along most of the margin of the inflorescence head bracts, rather than confined to a top section as in black knapweed

Go to Midwest Weeds and Wildflowers Home Page

Posted 23 January 2019