[The Knapweeds of Mt. Adams]
Spotted Knapweed

Centaurea macuolsa

The photo above shows the flower head of spotted knapweed as seen along Road #23 at the Mt. Adams Viewpoint about one-half mile south of Road #8810....................August 26, 2005. Note the long spine at the tip of each dark involucral bract, and the numerous comb-like lateral spines. See the lowest photo for a close-up of the involucral bracts.

The photo above shows one of the lowermost, pinnatifid leaves of spotted knapweed.

The upper most stem leaves are much reduced in size becoming trifoliate or simple with linear to slightly oblanceolate lobes or main section.

The photo above shows the branched form of the upper stem of spotted knapweed.

The photo above shows a pinnatifid leaf of a midstem leaf of spotted knapweed.

Note the dark-tipped involucral bracts with comb-like lateral bristles on the involucre of spotted knapweed.


Paul Slichter