Phosphorus sorption curves for evaluating phosphorus requirements of loblolly pine pinus taeda
Communications in Soil Science and Plant Analysis 13(8): 619-632
ISSN/ISBN: 0010-3624 DOI: 10.1080/00103628209367300
Bray P2, Mehlich 1 and Mehlich 2 methods identified soils on which loblolly pine would respond to P fertilizer in a greenhouse study using 6 soils from the West Gulf Costal Plain [USA]. The P extracted by any of the 3 methods did not correlate with growth on unfertilized soils or to the maximum amount of response when P was applied. P sorption curves were used to estimate the amount of P in soil solution. The concentration of P in roots and tops was proportional to the log of the amount of P in solution. For 90% of maximum dry weight of loblolly seedlings, .apprx. 0.22 mg/l of P in soil solution was necessary. The P sorption method was the potential of predicting the P requirements of loblolly pine, but field testing is necessary.