POTENTIAL FOR LEACHING OF POTASSIUM AND PHOSPHORUS FROM PINE AND GRASS-ROOTS

Nutrient analysis of roots recovered by wet sieving may be biased by l eaching which occurs during sampling. The objective of this experiment was to determine the potential for leaching of potassium (K) and phos phorus (P) from roots of slash pine (Pinus elliottii Engelm. var ellio ttii) and Panicum aciculare grass seedlings. Roots of both species wer e sampled by wet and dry methods. The wet method included soaking for 15 d in deionizd water. All samples were dried prior to measuring thei r contents of sand, K and P. The amount of sand retained by both types of roots was reduced by wet treatment. Concentrations of K and P in b oth species also were significantly lower for wet-treated roots than f or dry roots. Multipliers for converting concentrations in wet-treated roots to concentrations in dry roots were, for pine; 5.4 and 1.2 for K and P, respectively, and for grass 5.9 and 3.1 for K and P, respecti vely. However, these factors may be inappropriate for roots that had l ess exposure to water, or to roots of different anatomy and nutrient c oncentrations.