The Valencian Community is one of the main producers of rice and citrus in Spain. Rice straw (residue from rice paddy fields) is usually eliminated by controlled burning of crops. On the other hand, residues of citrus fruit pruning are also eliminated by burning or shredding in green and subsequent incorporation into the soil.
Dairy cattle and other ruminants are biologically designed to convert forages and other fibrous feeds into high quality products such as meat and milk. Forages are in general the least expensive source of energy for dairy cows. However, the efficiency of converting forages to milk is limited by the digestibility of forage cell walls.