_:b670469150 . _:b670469150 "Hauer RJ, Dawson JO, Werner LP (2006) Trees and Ice Storms - The Development of Ice Storm-Resistant Urban Tree Populations (2 ed.). College of Natural Resources, University of Wisconsin\u2013Stevens Point, and the Department of Natural Resources and Environmental Sciences and the Office of Continuing Education, University of Illinois at Urbana-Champaign. http://web.extension.uiuc.edu/forestry/publications/pdf/urban_community_forestry/trees_and_ice_storms_2006.pdf" . _:b670469150 . _:b670469150 . _:b670469150 "The U.S. National Weather Service defines an ice storm as a storm which results in the accumulation of at least 0.25-inch (6.4 mm) of ice on exposed surfaces." . _:b670469150 "https://en.wikipedia.org/wiki/Ice_storm" . _:b670469150 .