In 1902, faced with food crop devastation from a peak in the population of grasshoppers, Criddle developed a mixture of pesticidaltoxins called the "Criddle Mixture" to combat them, and was hired by the provincial government to demonstrate its use to farmers.[3] In 1913 the Manitoba government hired him as an entomological field officer, and in 1919 he was appointed the provincial entomologist.[4] Gifted with considerable artistic ability, Criddle illustrated a number of agricultural books; his and Dr. James Fletcher's Fodder and Pasture Plants and Farm Weeds of Canada are especially noteworthy.[citation needed]
^Bumsted, J. M. 1999. Dictionary of Manitoba Biography. Winnipeg: University of Manitoba Press, 1999. ISBN0-88755-169-6 (cloth), ISBN0-88755-662-0 (paper)
^Criddle, A. 1975. The Criddles of Aweme. The Manitoba Entomologist 8: 5–9.
^Gibson, A., and H. G. Crawford. 1933. Norman Criddle. The Canadian Entomologist 65:193–200.