NITROGEN-FERTILIZATION EFFECTS ON PLANTING STOCK CHARACTERISTICS AND ESTABLISHMENT PERFORMANCE OF DWARF ELEPHANTGRASS

'Mott' elephantgrass (Pennisetum purpureum Schum.) is a high-quality t ropical forage that is vegetatively propagated using stems or stem cut tings. Mott is more difficult to establish than tall elephantgrass, an d a better understanding is needed of management factors that affect i ts establishment. During 1987 through 1989, field studies were conduct ed On an Adamsville fine sand (hyperthermic, uncoated, Aquic Quartzips amment). Objectives were to determine the effect of N fertilization of planting stock nurseries on chemical and physical characteristics and establishment performance of Mott stems, and to determine if relation ships exist between planting stock characteristics and establishment p erformance. Nitrogen rates were 0, 50, 100, 200, 300, and 400 kg ha-1, and treatments were replicated twice for measurement of stem characte ristics and three times for establishment performance. Stem length (31 .0-40.5 cm), mass (10.4-14.8 g per stem), N concentration (8.9-16.0 g kg-1), N content (0.09-0.24 g per stem), and total nonstructural carbo hydrate (TNC) content (0.97-1.33 g per stem) increased linearly with i ncreasing N rate. Measures of establishment performance generally incr eased with increasing N rate in 1987 and 1989, years for which rainfal l was near or above normal during the time when planting stock was gro wing. Drought during this period in 1988 resulted in lower values for most stem characteristics and for measures of establishment performanc e. Highest correlation coefficients (0.53-0.60) were observed between number of emerged shoots per row and the stem characteristics, length, mass, and TNC concentration and content. These data indicate that N f ertilization of Mott nurseries (greater-than-or-equal-to 200 kg ha-1) and soil moisture during growth of planting stock are critical to subs equent establishment performance of planted stems, and that stem chara cteristics are correlated with establishment performance.