Response of green ash and white ash seedlings to ambient rain and ozone pollution in New Brunswick, New Jersey

Abstract

An experiment was conducted during the summers opf 1982-1984 at Cook College, New Brunswick, New Jersey, a site characterized by rainfall with an average pH of 4.2 and pollution episodes in which ozone exceeds 0.10 ppm. In 1982, two-year-old green ash (F. pennsylvanica) seedlings were grown in pots of unsterilized sandy loam in open top modules, half of which were supplied whith charcoal filtered air and half with ambient air. Within each module, half of the seedlings were protected during rain events by clear plastic umbrellas, and half were exposed to ambient rain. In 1983, the experimental design was modified. Green ash and white ash (F. americana) were used, and the ozone control was provided by weekly applications of a soil drench of 500 ppm ethylenediurea (EDU). Within each ozone treatment, half of the seedlings were protected during rain events by a plastic cover suspended over a wooden frame, and half were exposed to ambient rain. The white ash seedlings used in the 1983 experiment were maintained through the winter, and exposed to the same treatments in 1984. During the experiment, the amount of precipitation from each rain event was measured, and an equivalent amount of tap water was appliedmore » to the base of the seedlings not receiving ambient rain. From evidence accumulated over three years it is suggested that the growth of green and white ash is not, at least in the short term, adversely affected by ozone pollution or acid precipitation in New Brunswick, New Jersey. Although green ash foliage showed slight ozone injury one year and decreased chlorophyll content due to rain treatment in another year, these effects were not reflected in total growth. Ambient rain appeared to stimulate height growth and diameter growth of white ash.« less

Abstract from the paper’s OpenAlex record, shown for indexing and research. Copyright remains with the authors or the publisher. Read at the source ↗

The text the model read, with the source record’s inline markup (italics, sub- and superscripts) rendered and its character entities decoded; quote offsets refer to the raw text.