Oatmeal is a coarse grain, while leaf wheat is a fine grain. The difference between oats and oats is that oats are coarse grains, while oats are fine grains, and both have high nutritional value. Oats (scientific name: Avenasativa L.) is an annual herbaceous plant of the Gramineae family and the genus Oat. The fibrous roots are tougher. The stalk is upright, smooth and hairless, up to 120 cm high, and knotted.