In the summers of 1939 and 1940 hand defoliation oftrembling aspen, Populus tremuloides Michx., was carried on in a young stand located a few miles north of Itasca State Park. This study was undertaken to determine the response of aspen trees to several amounts of defoliation at four different times during the summer. Other similar artificial defoliation studies have been reported by Wallace (1945), Giese et al. (1964), Skilling (1964), Kulman (197 I), and Heichel and Turner (1976).
Hodson, A. C.
"The Response of Aspen (Populus Tremuloides) to Artificial Defoliation,"
The Great Lakes Entomologist: Vol. 14
, Article 7.
Available at: http://scholar.valpo.edu/tgle/vol14/iss3/7