SCIENCEGEEK ADVENT CALENDAR EXTRAVAGANZA! (DAY 7)
NITROGEN INCREASES FRESH WEIGHT AND RETAIL VALUE OF FRASER FIR CHRISTMAS TREES
(As measured by number of buds as well as weight, length, and surface area of needles)
Hinesley L.E. et al. HORTSCIENCE 35(5):860–862. 2000.
Abstract. Abies fraseri (Pursh) Poir. Christmas trees were fertilized for 5 years with four levels of N (0, 56, 113, or 170 kg·ha–1 per year) in spring, fall, or equally split between spring and fall. Nitrogen did not affect leader length, number of leaders, or bud frequency on the upper (distal) portion of the leader. Nitrogen increased bud frequency on the lower (proximal) 20 cm of the leader in only 1 of 3 years of measurement. All application schedules increased the number of apical buds on branches, whereas the number of lateral buds was increased only by spring applications. Nitrogen increased tree fresh weight and retail value as well as weight, length, and surface area of needles. Foliar N concentrations in the fall varied with fertilization schedule, and were higher in November than in October.