Pignut plant and edible tuber
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The nutty-tasting root tubers of Conopodium Majus, found growing in woodlands from May to July. Eaten raw or roasted.
Nicholas Culpeper's 'Complete Herbal' of 1653 has; "Pignuts: A description of them were needless, for every child knows them. Government and virtues: They are something hot and dry in quality, under the dominion of Venus; they provoke lust exceedingly, and stir up those sports she is mistress of; the seed is excellent good to provoke urine; and so also is the root, but it does not perform it so forcibly as the seed doth."
In Shakespeare's 'Tempest' (II;2) Caliban offers to;
let me bring thee where crabs grow;
And I with my long nails will dig thee pig-nuts.
Original Receipt in 'Acetaria: A Discourse of Sallets' by John Evelyn (Evelyn 1699)Earth-Nuts, Bulbo-Castanum; (found in divers places of Surry, near Kingston, and other parts) the Rind par'd off, are eaten crude by Rustics, with a little Pepper; but are best boil'd like other Roots, or in Pottage rather, and are sweet and nourishing.