diffuse knapweed
Centaurea diffusa Lam.


Centaurea diffusa is a biennial, annual, or short-lived perennial that is 8-40 in. (20.3-101.6 cm) tall.
The leaves are stalked and lobed. The leaves become smaller and less divided as they move up the stem.
Flowering occurs from July to September. White flowers develop in urn-shaped heads, in clusters, at the ends of the branches. The heads are subtended by leathery bracts. The lower and middle bracts have brown margins with spines at the tips.
Seeds are achenes, 0.08-0.12 in. (2-3 mm) long with a plume of bristle-like hairs.
Ecological Threat
This species prefers well drained soils, gravel pits, trails, pastures and roadsides.


Selected Images


EDDMapS Distribution

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

State Regulated List

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

Taxonomic Rank

Kingdom: Plantae
Phylum: Magnoliophyta
Class: Magnoliopsida
Subclass: Asteridae
Order: Asterales
Family: Asteraceae
Genus: Centaurea
Subject: Centaurea diffusa Lam.

Synonyms and Other Names

Other Common Names:
white knapweed

Related Scientific Names:
Acosta diffusa Lam. (Synonym)


Plants - Forbs/Herbs