Abstract
Abstract Nitrogen (N) and phosphorus (P) concentrations in the roots and foliage of plantation-grown loblolly pine were examined over a period of 18 months. Samples were collected from 4 sites on the lower coastal plain of North Carolina, each representing a distinct combination of soil moisture and soil fertility. The patterns in foliar and root nutrient concentrations followed similar trends over the course of this study. However, seasonal trends were irregular, suggesting that annual climatic variation may affect seasonal nutrient levels. Nutrient concentrations varied among sites, as did effects of fertilization (225 kg N ha -1, 225 kg N ha -1 + 75 kg P ha -1) on nutrient concentrations. Significant fertilizer effects on nutrient concentrations did not always result in increased volume growth. On some sites, root N and P concentrations appeared to be more sensitive to fertilizer-induced changes than did foliar nutrient levels and may have integrated site factors more effectively than foliar concentrations. Foliage seemed more sensitive to N deficiencies, while the roots detected P deficiencies more often. For. Sci. 33(4):984-996.
Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
