Studies to assess the effects of ozone on native vegetation of Acadia National Park: 1993 annual report

Eckert, Robert; Kohut, Robert; Lee, Thomas; Laurence, John; King, Paul; Stapelfeldt, Karen; Raba, Richard

From the summary: 'Air quality research at Acadia National Park in 1993 continued to assess the relative sensitivity to ozone of native species of vegetation, and the ambient ozone regimes at the fumigation site near Sand Beach and at the summit of Cadillac Mountain.' 'During the four years of this study, more than 32 species of plants native to ACAD have been subjected to controlled ozone exposures. We can draw some conclusions about the following 26 species. Species injured at ambient levels of ozone were black cherry (Prunus serotina), quaking aspen, white ash, big-leaf aster (Aster macrophyllus), and spreading dogbane. These is some indication that red maple (Acer rubrum), mountain ash, pin cherry, mountain holly, three-toothed cinquefoil, and flat-topped aster may also be injured at ambient levels of ozone, but additional confirmation is required. Species which showed foliar injury at levels of ozone slightly greater than ambient were jack pine (Pinus banksiana), gray birch (Betula populifolia), small sundrops (Oenothera perennis), and bunchberry (Cornus canadensis). White pine, paper birch (Betula papyrifera), pitch pine (Pinus rigida), red spruce (Picea rubens), northern white cedar (Thuja occidentalis), northern red oak (Quercus rubra), Canada blue-joint grass (Calamagrostis canadensis), wild radish (Raphanus raphanistrum), staghorm sumac (Rhus typhina), wild sarsaparilla, and Canada mayflower (Maianthemum canadense) remained uninjured at all levels of exposure.' 'As the logical extension of the controlled ozone exposure studies, field assessment of potential ozone indicator species has been initiated at ACAD. Our objectives were: (1) to determine if visible ozone injury had occurred in natural populations of eight native plant species at ACAD as of August, 1993, and, (2) to determine the feasibility of assessing ozone injury using a pointbased system of sampling.' 'Eight species, selected on the basis of their sensitivity to ozone, symptom expression in the fumigation studies, and distribution within the Park, were surveyed in the field. Nearly 1,200 plants were examined during the quantitative survey, which took place in mid-August. Of these, only one individual exhibited visual symptoms of ozone damage. The lack of ozone injury in the Park is consistent with the low ozone levels recorded during 1993 growing season. The lone symptomatic plant was a dogbane ramet located just south of the summit of Great Hill.' /STUDY LOCATIONS:/ /ACADIA NATIONAL PARK/