Bristly Oxtongue (Helminthotheca echioides) is a common wayside plant in Huntingdonshire, less so in Mid-West Yorkshire. The common plant of disturbed and semi-natural habitats is var. echioides with its dull, floppy, pale-green leaves. However, occasionally you come across a plant that looks a bit different and when it occurs as a large colony, such as at Warren Hill, Kimbolton (VC31) there can be no doubt that it is different. This is var. pratensis which is distinguished by its narrower, shiny coriaceous leaves and more obvious prickles. The stem is often red-tinged. It seems to be a short-lived casual and rarely persists for long at locations where it is out-numbered by var. echioides. In such circumstances, the two varieties seem to interbreed and produce variable offspring showing traits from both parents.
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