Wheatgrass essentially IS wheat (wheat greens, that is). However, it contains no wheat gluten if that's what you're afraid of. You can probably eat it even if you have a wheat allergy.
Wheat is a major ingredient in such foods as bread, porridge, crackers, biscuits, Muesli, pancakes, pies, pastries, cakes, cookies, muffins, rolls, doughnuts, gravy, boza (a fermented beverage), and...