Pie pumpkins are any one of several varieties of pumpkin grown for eating rather than decorative purposes. Generally, they are smaller and more dense than decorative pumpkins. Recipes calling for pumpkin may use canned or fresh varieties, but should never have decorative pumpkins used as a substitute.  Pie pumpkins are an excellent source of beta carotene, calcium and potassium. For vegetarians, it can make an excellent replacement for meat in winter stews and soups. Many people consider pumpkin pie to be the essence of fall, reminding them of crisp falling leaves, cool evenings and the approaching holidays.