These are the leaves of Sheep Dock or Sheep Sorrel (Rumex acetosella). The plant's pinky-sized leaves feature flared lobes and pack a sour punch (other names include Sour-weed and Sour Grass). They can be added to salads and soups, or dried and steeped for tea. For a thorough discussion of Sheep Dock, consult Edible Wild Plants: Wild Foods from Dirt to Plate by John Kallas. He devotes a dozen pages and more than a dozen vibrant photos to today's featured wild food. Among other tips, he recommends removing the stringy leaf stalks before chowing down.