in Thoreau’s Journal:

Passing over the Great Fields (where I have been surveying a road) this forenoon, where were some early turnips, the county commissioners plucked and pared them with their knives and ate them. I, too, tried hard to chew a mouthful of raw turnip and realize the life of cows and oxen, for it might be a useful habit in extremities.

These things occur as the seasons revolve. These are things which travellers will do.  How many men have tasted a raw turnip! How few have eaten a whole one! Some bovine appetites, which find some fodder in every field. For like reasons we sometimes eat sorrel and say we love it, that we may return the hospitality of Nature by exhibiting a good appetite.