Fertilizer Nitrogen Uptake and Partitioning in Young and Mature Common Hackberry (Celtis occidentalis) Trees    (View PDF)

L.P. Werner and L.G. Jull

Abstract: Twenty-one mature and thirty-six young common hackberry (Celtis occidentalis L.) trees received a single application of 15N double isotope enriched ammonium-nitrate (NH4NO3) fertilizer. Application rates were 0, 0.49, and 1.47 kg N 100 m-2 of canopy coverage, respectively. Foliage, current season stem wood, stem wood, root, and fruit tissues were analyzed for total concentration [N] and nitrogen derived from fertilizer (NDFF). Growth phase and application rate did not consistently affect total % [N], particularly the N demanding foliage. Growth phase and application rate significantly affected the percentage of NDFF. In every instance, NDFF was highest in the tissues of young trees and/or trees receiving the 1.47 kg N 100 m-2 application rate. Mature trees relied upon previously assimilated N to meet the annual demand for N to a greater extent than young trees.

Keywords: ANSI A-300; Celtis occidentalis; Fertilization; Hackberry; Nitrogen; Remobilization

https://doi.org/10.48044/jauf.2013.012