Received for publication May 6, 1981. This project was financed in part with Federal funds from the Environmental Protection Agency under grant number R803971, by the Wisconsin Public Service Corporation, Madison Gas and Electric Company, Wisconsin Power and Light Company and by the College of Agriculture and Life Sciences, University of Wisconsin. The contents do not necessarily reflect the views or policies of the Environmental Protection Agency, Department of Horticulture, University of Wisconsin or the above corporations, nor does mention of a trade name for a commercial product constitute endorsement or recommendation for use.
The cost of publishing this paper was defrayed in part by the payment of page charges. Under postal regulations, this paper therefore must be hereby marked advertisement solely to indicate this fact.
National Research Council, Postdoctoral Research Associate, United States Environmental Protection Agency, Corvallis Environmental Research Laboratory, Corvallis, OR 97333; and Professor, Department of Horticulture, University of Wisconsin, Madison, WI 53706, respectively.
The authors express appreciation to Janice Kobriger for advice and information pertaining to dry weight lost during extraction of chlorophyll from pea leaves.