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It would be easy to overlook Sherardia arvensis, or field madder, as both the leaves and flowers are very small. However, it is widespread across most of Europe, including Britain, and often found in well drained fields, sand dunes and disturbed ground. The bristly leaves are found in whorls of 4-6 around the square stem, growing to ~1cm, while the 3mm, four-petalled flowers are pale lilac or pink. The roots can be used to produce a red dye. The Latin name is in honour of a 17th Century Leicestershire botanist, William Sherard.
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