Nitrogen Accumulation and Use by a Young Loblolly Pine Plantation in Southeast Oklahoma: Effects of Fertilizer Formulation and Date of Application
Authors: Blazier, Michael A.; Hennessey, Thomas C.; Dougherty, Philip; Campbell, Robert
Source: Southern Journal of Applied Forestry, Volume 30, Number 2, May 2006 , pp. 66-78(13)
Abstract:
Practices that enhance crop tree nitrogen (N) accumulation and use improve the efficiency of forest fertilization operations. This study was established to explore the N accumulation and use by a young loblolly pine plantation in response to (1) season of fertilizer application, (2) herbaceous vegetation suppression, and (3) fertilizer formulation. Water-soluble and slow-release urea formulations were applied to single-tree plots in January/February, April, June, August, and October of 2001 and 2002. Herbaceous vegetation was suppressed where appropriate with glyphosate. Foliage N accumulation was measured 1 and 2 months after fertilization; N use efficiency was measured 1 year after fertilization. Between 0.3 and 8.0% of applied N was recovered by the foliage within 1 month of application and 7–26% of applied N was used for stem growth within 1 year of application. In both years of this study, summer and fall applications produced the highest N accumulation and use. Suppressing herbaceous vegetation enhanced N accumulation and use when the plantation was 3 years of age (with an average tree height of 6 ft in January 2001). N accumulation and use of slow-release urea was similar to or lower than that of water soluble urea in both years of the study.Keywords: Nutrient management; herbaceous vegetation control
Document Type: Research article
