Middleton, W. 1933 The scope of shade-tree and hardy-shrub insect problem with special reference to the conditions found in 1932.. 9th National Shade Tree Conference, Proceedings (Sept. 7-8, 1993) 73-85.

Notes: Insects mentioned include Euonymus scale, oyster shell scale, pine leaf scale, juniper scale, cottony maple, Kermes, Tulip soft scale, Magnolia soft scale, European elm, Gloomy scale, San Jose scale, Maple phenacoccus, Aspidiotus sp., A. juglans-regiae, Aulacaspis pentagona, European fruit lecanium, elm scurfy scale, obscure scale, Aulacaspis rosae, terrapin scale, golden oak, Chionaspis spp., Aspidiotus ancylus, Asterolecanium spp., Pulvinaria spp., Lecaniodiaspis spp., Lecanium quercifex, Leucaspis spp., and cottony cushion scale.