KelsaeJohn's picture

Uncommon Knapweed

Observed: 12th August 2008 By: KelsaeJohnKelsaeJohn’s reputation in PlantsKelsaeJohn’s reputation in PlantsKelsaeJohn’s reputation in PlantsKelsaeJohn’s reputation in Plants
Brown Knapweed?

This Knapweed (foreground) grew every year on my former 'Local Patch' and was the only one of it's kind I ever saw. Common Knapweed (Centaurea nigra) was very common and widespread in the area. This particular plant grew alongside a National Cycle Track (formerly a railway-line) and grew in well-drained conditions close to the base of a Goat Willow (Salix caprea)

Species interactions

No interactions present.

Species with which Common Knapweed (Centaurea nigra) interacts


Duxbury Rambler's picture

The stem looks swollen below

The stem looks swollen below the flower to me so I am thinking the rayed form of common knapweed. Any more photos John?

KelsaeJohn's picture

Knapweed spp.

Thank you for your interest Carol. I do have one or two more pics although I am not sure how helpful they will be. I only came across these pics this afternoon (printed from files on a previous PC. I will have to scan them and will post them ASAP.
PS - although these pics were taken some time ago I seem to remember noting that there was something about the structure of the leaves and stems that led me to exclude Greater Knapweed. Sorry I can't be more helpful.

KelsaeJohn's picture

Uncommon Knapweed

Given the uncertainty with regard to this particular picture I wonder if anyone has given any thought to the possibility that it might be Brown Knapweed (C. jacea)? This spp is an introduction to the British Isles. Although it is listed as very rare, I am still prepared to consider the possibility. As I said in my original post, C. nigra was very common and widespread but in all the years I explored that area I never came across another plant that looked anything like this one.

Refugee's picture

The lighting

The sun it in front of the camera and i went for Greater. If there is a confusion one than that it likely....
The buds are quite hard to see in the photo.
I will hill have to wait until the summer again and have an other look at my local patch. There might be more than just common and greater there.

Have a look....