In a greenhouse experiment conducted to determine the relationship of nitrogen, phosphorus, and potassium supply to slash pine seedling yield and composition, 30 combinations of N, P, and K were supplied to the seedlings for a four-month growing period. Seedling yield and composition were found to be closely associated with nutrient supply. Fresh weight, dry weight, and height growth were indicated by regression analyses to be maximum when the nutrient supply of N and K is greater than 125 ppm, but less than 625 ppm. Maximum response to phosphorus was not reached at 125 ppm, the highest concentration supplied. The concentration of N, P, or K in the seedling tissue increased as the supply of the respective element was increased.
Document Type: Journal Article
Research Forester, Southeastern For. Expt. Sta., Forest Service, U.S. Dept. Agric.