The Certified Arborist credential identifies professional arborists who have a minimum of three years' full-time experience working in the professional tree care industry and who have passed an examination covering facets of arboriculture.[1][2] The Western Chapter of the International Society of Arboriculture (ISA) started the certification program in the 1980s,[citation needed] with the ISA initiating it in 1992.[3]
^Konijnendijk, Cecil C.; Randrup, Thomas B. (2005). "Urban forestry education". In Konijnendijk, Cecil C.; Nilsson, Kjell; Randrup, Thomas B.; Schipperijn, Jasper (eds.). Urban Forests and Trees: A Reference Book. Berlin: Springer. p. 470. ISBN9783540276845.
^Koeser, Andrew K.; Hauer, Richard J.; Miesbauer, Jason W.; Peterson, Ward (2016). "Municipal tree risk assessment in the United States: Findings from a comprehensive survey of urban forest management". Arboricultural Journal. 38 (4): 218–229. doi:10.1080/03071375.2016.1221178.