There are 2 types of hay - legumes (alfalfa and clover) and grasses which include cereal grains (Timothy, oat, fescue, coastal bermuda, rye, etc.). Different hays are available at different times of year and different areas. Grass hays are high in fiber but lower in nutrients. Legumes are rich in nutrients, So a combination of hays is important. Make sure to purchase high quality hay from a reliable dealer. Check bales for mold or dampness.