Southern Marsh Orchids

Southern Marsh Orchids

Monday, 22 June 2015

White Colour Disease of Creeping Thistle.

Last summer, while lurking around Pwll Waun Cynon nature reserve, in the Cynon Valley, I noticed that several of the shoots of Creeping Thistle, in an otherwise healthy population, were startlingly creamy white; obviously lacking in chlorophyll. I checked for rusts, and found none present.

Yesterday, I called in to PWC again and saw that there were several chloritic shoots present once more, in the same area of the reserve.

White-colour Disease in Creeping Thistle


I had a search online and found this interesting article on the subject. It would be useful, I think, to keep a record of any such plants we come across.  http://www.llanellinaturalists.org.uk/index.php/March-2009/the-mystery-of-the-qwhiteq-thistles.html

2 comments:

  1. Interesting, I've seen this a couple of times in recent years but annoyingly I haven't made a note of where and when. I'd never have guessed it was bacterial, or that it was such a recent arrival in the UK.

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  2. Me neither. When I could see that it wasn't caused by a rust, I assumed it must be a virus, as many variegations of garden plants are due to viruses.

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