Very variable in height, this plant has slender, spineless, unwinged stems, whilst the "Saw" of Saw-wort refers to the serrated edges of its narrow leaves. Flowerheads are purple, and rather thistle like, rayless, in branched clusters. Flower bracts purplish, erect.

Centaurea (knapweeds)

Smaller than knapweeds, with many rows of phyllaries (bracts under the flowerhead), which are entire, and acute.  Lower leaves usually lobed to midrib. 

A photograph of the whole plant, showing lower leaves and a side-on view of flowers (RPR).

Old grassland and meadows, woodland margins, on slightly acid to calcareous soils.

Flowers July to September.

Perennial.

Widespread but local in England and Wales.

Scarce and decreasing due to habitat loss in Leicestershire and Rutland.

In the VC55 checklist (Jeeves, 2011) it is listed as Native; old grassland; recorded from c. 100 localities; now scarce.