New Diseases and Epidemics Regional Effects of Sulfur Dioxide and Ozone on Eastern White Pine (Pinus strobus) in Eastern Wisconsin. C. L. Rezabek, Bureau of Air Management, Wisconsin Department of Natural Resources, Box 7921, Madison 53707. J. A. Morton, E. C. Mosher, A. J. Prey, and J. E. Cummings Carlson. Bureau of Air Management, and Bureau of Forestry, Wisconsin Department of Natural Resources, Box 7921, Madison 53707. Plant Dis. 73:70-73. Accepted for publication 27 June 1988. This article is in the public domain and not copyrightable. It may be freely reprinted with customary crediting of the source. The American Phytopathological Society, 1989. DOI: 10.1094/PD-73-0070.

Between 1 July and 25 September of 1985, 10,706 white pine (Pinus strobus) at 109 study sites in 30 counties of eastern Wisconsin were surveyed for tipburn and mottling. Tipburn and mottling are visible symptoms of air pollution (sulfur dioxide [SO₂] and ozone [O₃]) injury. White pine study sites in the southeast and east central regions had higher percentages of tipburn and mottling than those in the northeast region of the state. The occurrence of tipburn and mottling is associated with the relatively high SO₂ and O₃ levels in the southeast region of Wisconsin. Tipburn and mottling were found to be related to one another. Tipburn and mottling were also found to be significantly (P = 0.001) related to the absence of adjacent vegetation.