Young horsetail shoots (Equisetum arvense) are an edible wild food, fine for foraging when they are young. They look pretty much as they were in the Paleozoic era but considerably smaller.
Remove the sheath from over the knobbly joints first. Blanch in boiling water to which you have added 2 tsp vinegar and 1 tsp salt per litre. After 30 seconds in the boiling water, remove and plunge into cold water for a couple of minutes. Remove and gently pat dry with kitchen paper. Then fry in oil or butter until just crisping with a final sauté in a little dry sherry.