Marsh marigolds (Caltha palustris), Lydiard Park, Swindon
Introduction
The photograph on this page of Marsh marigolds (Caltha palustris), Lydiard Park, Swindon by Brian Robert Marshall as part of the Geograph project.
The Geograph project started in 2005 with the aim of publishing, organising and preserving representative images for every square kilometre of Great Britain, Ireland and the Isle of Man.
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Image: © Brian Robert Marshall Taken: 12 Apr 2009
Marsh marigolds or kingcups are herbaceous perennial plants that grow in shady, damp areas. They are members of the buttercup family and grow widely in the northern hemisphere. The plants have long been established in the UK, surviving the harsh conditions of the last ice age. The flowers are undoubtedly attractive but excessive handling of the plants can cause skin rashes as all parts are irritant. The flies are possibly Sphegina montana but perhaps not. The name doesn't sound very British. Whatever they are they are essential to the pollination process and the flowers contain attractants to lure the flies. The relationship between plant and insect is mutually beneficial. In the UK there are two subspecies, Caltha palustris subsp. palustris, and Caltha palustris subsp. minor. Lord only knows which one this is; I've no idea. The technical information above came from wikipedia.