Assistant Professor of Ornamental Horticulture, Univ. of Florida, Gainesville, FL 32611.
Former Graduate Associate, Dept. of Agronomy.
Associate professor of Horticulture.
Professor of Horticulture.
Received for publication 21 Mar. 1988. Technical Contribution no. 2853 of the South Carolina Agricultural Experimental Station, Clemson Univ. 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.