Vol. 110 (1997): Proceedings of the Florida State Horticultural Society Vegetable Influence of Smooth Pigweed and Common Purslane Densities on Lettuce Yields as Affected by Phosphorus Fertility PDF B. M. Santos, J. A. Dusky, W. M. Stall, D. G. Shilling, T. A. Bewick Published 1997-12-01 PDF