trifolium subterraneum

Trifolium subterraneum, the subterranean clover (often shortened to sub clover), subterranean trefoil, is a species of clover native to northwestern Europe, from Ireland east to Belgium. The plant's name comes from its underground seed development (geocarpy), a characteristic not possessed by other clovers.

It can thrive in poor-quality soil where other clovers cannot survive, and is grown commercially for animal fodder. There are three distinct subspecies used in agriculture, each with its own ideal ...