Defoliation : An unseasonable reduction in the foliage cover of a plant due to attacks by insects or fungal disease, or as a result of other factors such as drought, storms, or chemicals in the atmosphere
British Columbia Ministry of Forests and Range, Acronyms and Initialisms for Forestry Terms in British Columbia, Canada 2008. http://www.for.gov.bc.ca/hfd/library/documents/acr onyms/ & http://www.for.gov.bc.ca/hfd/library/documents/glo ssary/Glossary.pdf, (For Fr - Canad) {16}