Pig nut is another one of the umbellifers, quite a liitle plant and one which can tolerate fairly dark conditions. So I would say it is a proper woodland species, it probably would not grow in hedgerows as taller grasses and plants like Cow parsley, Stinging nettles and Red campion would swamp it.
As the name suggests it is edible and the ‘nut’ is in fact a tuber and found underground. I must confess I have never bothered to dig one up but they are supposed to be quite acceptable. In general I do not approve of digging up and disturbing wild flowers. Foraging on this plant will destroy it whereas taking a few leaves from something like wild garlic to add to a stew or blend into a soup will not do it any permanent damage. I always remember my Mother telling me that they used to gather baskets full of Cowslip flowers to make wine when she was younger… then she would add, but now of course you hardly ever see any!!! Whether it was the collection that resulted in their scarcity or changes in farming practice or herbicides I don’t know, probably a combination but certainly gathering them by the basket full would not have helped.
There is a foraging web site which will tell you all about the cullinary properties of Pig nuts, how to dig them up, prepare them and cook them… should you be interested. They are not rare so a one off taster will not do any great harm. The site is called Paul Kirtley’s Blog and is has Bushcraft and Survival articles.
The ‘nut’ is buried quite a way down so you have to be careful when digging it up, something which Paul Kirtley explains in some detail. No doubt this is beneficial to the plant as it makes extracting it quite difficult, thus protecting it from smaller foragers like squirrels, mice and hedgehogs. Obviously larger mammals like Pigs, Badgers and where I live wild Boar will be easily able to dig down the 15 to 20 cm or so required to gain access. However despite there being lots of Boar living in the Forest of Dean there are also lots of Pig nuts, so they have not had much effect on their population. Maybe in time it will start to affect them, the Boar have only been around a few years There were two releases one in the 1990’s. One near Ross on Wye and a second in 2004 near the village of Staunton and now they are everywhere.
The flowers are out in May and June, typical little white umbels, but unlike many species in this group the outer florets in the umbell do not have larger petals than the florets in the centre, they all seem to be roughly the same size. The leaves are very fine and quite dark green almost asparagus like, not so much like the ‘ferny’ leaves of Cow Parsley.