Web Directory

» A Close-up View of Brown Knapweed
   Photographic study by Brian Johnston of Centaurea jacea, with many fine images of the flowers, and microscopic images of the inflorescence and pollen grains.
   http://www.microscopy-uk.org.uk/mag/artmar06/bj-knapweed.html

» Centaurea calcitrapa
   Red Star-Thistle. Detailed plant classification, national distribution maps, status as invasive plant and noxious weed. From the USDA PLANTS data base.
   http://plants.usda.gov/java/profile?symbol=CECA2

» Centaurea cyanus
   Photograph, systematic position, morphology, biology, distribution, ecology and economic significance of the Cornflower.
   http://www.agroatlas.ru/weeds/Centaurea_cyanus_en.htm

» Centaurea nigra
   Several fine photographs of Knapweed and some identifying features.
   http://www.plant-identification.co.uk/skye/compositae/centaurea-nigra.htm

» Centaurea tauromenitana
   Image of plant, close-up of flower head.
   http://www.dipbot.unict.it/orto/0440-1.html

» Cornflower or Bachelor's Buttons: Centaurea cyanus
   Photographs of varying stages in the growth of this annual plant with its description and identifying characteristics.
   http://www.ppws.vt.edu/scott/weed_id/cency.htm

» Purple Starthistle Identification
   Identifying photographs for Centaurea calcitrapa. From King County, Washington, Department of Natural Resources.
   http://www.kingcounty.gov/environment/animalsandplants/noxious-weeds/weed-identification/purple-starthistle.aspx

» Spotted Knapweed or Star Thistle: Centaurea maculosa
   Photographs of varying stages in the growth of this biennial plant with its description and identifying characteristics.
   http://www.ppws.vt.edu/scott/weed_id/cenma.htm