Plant and Animal Sciences

" While most experimental studies of the effect of acid rain on plants have been carried out on single species, the real world contains many species of plants in competitive juxtaposition. Experiments on white clover and rye grass show that the outcome of acid rain treatment depends on such factors as the relative density of the two species and the timing of the application of acid rain.

L. Menchaca, M. Homung, “Response of white clover (Trifolium repens L.) and ryegrass (Lollum perenne L.) to acid rain in situations of species interferences,” New Phytologist 111,483-9, March 1989. (Institute of Terrestrial Ecology [NERC], Bangor Research Station, Gwynedd, and Merlewc~od Research Station, Cumbria, U.K.)

" Precisely what limits photosynthesis in a plant is an important question but one that is difficult to answer,...