Title: Premature Needle Loss of Spruce

Author: Juzwik, Jennifer; O Brien, Joseph G.

Year: 1990

Publication: NA-PR-01. [Radnor, PA]: U.S. Dept. of Agriculture, Forest Service, Northern Area State & Private Forestry

Abstract: Premature needle loss on white, black and Norway spruce has been observed in forest plantations in Wisconsin and Minnesota during the past six years. Symptoms vary by species but usually appear first in 2-4-year old needles on lower branches. Infected needles are dropped, resulting in branch mortality that progresses upward through the crown, sometimes killing even large, dominant trees. Several insects and fungi, as well as abiotic stresses such as drought and poor soils, appear to contribute to the damage. The fungus Rhizosphaera kalkhoffii is the only organism that has, been consistently associated with needle loss. R. kalkhoffii is commonly found on ornamental blue spruce throughout Minnesota and Wisconsin.