Chlorosis is a disease of plants, the characteristic symptom of which is the yellowing of the leaves. The disease is of sporadic but widespread distribution in Utah and the aggregate losses caused by it are undoubtedly greater than those of any other one disease. Not only are many plants killed, or weakened to such an extent that only inferior crops are produced, but many areas of land which might otherwise support profitable orchards have been abandoned or planted to other crops because of the disease.
Wann, F. B., "Circular No. 85 - Chlorosis Yellowing of Plants: Cause and Control" (1930). UAES Circulars. Paper 77.