Canadian Forest Service Publications
Evaluation of Aerial Forest Pest Damage Survey Techniques in British Columbia. 1979. Harris, J.W.E.; Dawson, A.F. Environment Canada, Canadian Forestry Service, Pacific Forest Research Centre, Victoria, BC. Information Report BC-X-198. 22 p.
Issued by: Pacific Forestry Centre
Catalog ID: 3939
Availability: PDF (download)
Detection and appraisal of forest pest damage in British Columbia is done, in part, by aerial surveys from small aircraft. Observers sketch areas of forest that are defoliated, discolored, or have dead trees onto topographic maps; they estimate the numbers of affected trees and sometimes take photographs for more detailed examination. A study comparing sketch-mapping and aerial photography showed that the two methods often yielded different results. Surveys using either method were useful if one understood their limitations. Improved sketch-mapping procedures, supplemented by aerial photography, should continue to be a useful forest pest survey technique.