|
|
Knapweed, Black (Centaurea
nigra LINN.) Click on graphic for larger
image |
Knapweed, Black
Botanical: Centaurea nigra (LINN.) Family: N.O. Compositae
Centaurea nigra, the Black Knapweed, is a perennial, with an
unwinged, erect stem, 6 inches to 3 feet high, generally freely branched
in the upper part. The leaves are very variable, both in breadth and
degrees of division, the upper ones narrow and generally with entire
margins, but the lower ones lobed, or at any rate with some coarse teeth.
The whole plant is dull green, rather rough with small hairs, the stems,
like the preceding species, very tough. The flowers are without the
spreading outer rays of the Greater Knapweed, the florets being all
tubular, which makes the black fringes to the bracts of the involucre most
noticeable, hence the name of the species. The florets are of a less
bright purple in colour.
|