Effects of post-budset fertilization on second-crop black spruce container stock

Abstract

Second crop black spruce (Picea mariana (Mill.) B.S.P.) container stock is often treated with finisher fertilizer after the induction of budset. The objective of this experiment was to study the effect of three components of a finisher fertilizer (monoammonium phosphate, potassium nitrate and potassium sulphate) on bud development, root development and the induction of cold hardiness in second-crop black spruce container stock. Fifteen fertilizer treatments were applied to black spruce seedlings at three private seedling growers in the fall of 1988. The analysis showed no significant difference in bud and root development among the fertilizer treatments. However, the fertilizer treatments may have had a small effect on the induction of cold hardiness. The hardiest seedlings in the experiment were treated with a fertilizer high in phosphorus and ammonium. A response surface analysis indicated that seedling hardiness may be further improved with fertilizer combinations outside of the experimental region in the direction of the strongest response.