Crop diversity fruit trees and banana plants) are cloned. A single pest or disease could threaten a whole crop due to this uniformity ("genetic erosion"). A well-known historic case was the Irish Potato Famine of 1845-1847, where a vital crop with low diversity was destroyed by a single fungus. Another example is when a disease caused by a fungus affected the monocultured 1970 US corn crop, causing a loss of over one billion dollars in production. A danger to agriculture is wheat rust, a pathogenic fungus causing reddish patches, coloured by its spores. A virulent form of the wheat disease, stem rust,
Crop destruction Crop destruction Crop destruction is the deliberate destruction of crops or agricultural products to render it useless for consumption or processing. It can be made by burning, grinding, dumping into water, or application of chemicals. It should not be confused with crop residue burning, which burns useless parts of the crop. Related to crop destruction is alternate, low-price use of agricultural products. A large portion of the wine lake (European Union wine surplus) is converted to industrial ethanol. There can be numerous reasons for crop destruction. In scorched-earth strategy, crops and other useful materials are destroyed to prevent the enemy