Intensive research over the last 20 years has shown that many of the previously unexplained and seemingly mysterious disorders of stone fruit trees in Utah are infectious diseases caused by viruses. Others were shown to be the result of noninfectious genetic abnormalities or of adverse chemical and physical factors in the environment of the plant. The purpose of this handbook is to help orchardists and others recognize these diseases and disorders and understand better their etiology or cause. The handbook will also bring together basic information which will aid in their control.
Richards, B. L. and Cochran, L. C., "Bulletin No. 384 - Virus and Viruslike Diseases of Stone Fruits in Utah: A Handbook for Their Identification and Control" (1956). UAES Bulletins. Paper 344.