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Restharrow (Ononis repens)

A characteristic plant of sand dunes where its dense, wiry network of roots serves to secure it to the ground but in arable land creates problems with tilling the soil - hence its name, as in the days of horse-drawn cultivation, the roots of this plant would, quite literally, 'arrest' the progress of the implements. The obstacle it presented to ploughing also accounts for its Welsh names hwp yr ychen or tag yr aradwr.
The generic term Ononis comes from the Greek 'onos', the donkey, of which it is a favourite food; restharrow has several medicinal uses too.