COMPOSITAE (COMPOSITE FAMILY) 521 



BROWN KNAPWEED 

 Centaiirea Jdcea, L. 



Other English names: Rayed Knapweed, Brown Centanry. 

 Introduced. Perennial. Propagates by seed. 

 Time of bloom : June to September. 

 - Seed-time : Late July to November. 

 Range: New England States, southward to New Jersey. 

 Habitat: Fields, pastures, and waste places. 



An immigrant from Europe not yet very widely disseminated in 

 this country. Stems, several from the same thick, woody, branch- 

 ing root, erect, stiff, grooved, slender, one to two feet in height, 

 branching near the top. Leaves narrowly lance-shaped, the lower 

 ones sparsely toothed and tapering to a petiole, the upper ones 

 entire and sessile. Heads showy, an inch or more broad, with 

 rosy purple corollas, all tubular but the outer row with enlarged 

 and lengthened lobes, simulating rays ; these showy florets are 

 sterile ; involucres nearly globose, the bracts closely imbricated, 

 glossy dark brown, the outer row fringed, the middle ones slightly 

 lacerate, the inner ones entire or nearly so. Achenes four-sided 

 and without pappus. 



Means of control 



Prevent seeding by cutting while in early bloom, and, if the area 

 infested is small and the plants are not too numerous, grub out or 

 hand-pull the perennial roots when the ground has been softened 

 by rain. Otherwise they may be destroyed by putting the land 

 under cultivation. 



BLACK KNAPWEED 

 Centaiirea nlgra, L. 



Other English names : Horse-knobs, Hardheads, Loggerheads, Hurt- 

 sickle, Spanish Buttons, Black Centaury. 

 Introduced. Perennial. Propagates by seeds. 

 Time of bloom : July to September. 

 Seed-time: Late August to November. 



Range: Newfoundland to Ontario, and southward to New Jersey. 

 Habitat: Fields, pastures, roadsides, and waste places. 



