Occasionally, observations of White Spruce (Picea glauca) or Colorado Spruce (Picea pungens) within landscapes, nurseries, & Christmas tree farms will show current needle growth having a blue or blue-green color, but with older, inner needles having lost the desirable color and turning pale or even yellow. Although sometimes seen on Norway Spruce, these symptoms are most common on the White & Colorado Spruce species. Sometimes symptoms can become dramatic and initiate both aesthetic and plant health concerns. Although the reasons for such symptoms can be from a complex number of conditions, a compromised root system is typically the underlying cause.
Colorado Spruce showing symptoms of undesirable discoloration of older, inner needles. Photo Credit: Steven K. Rettke of Rutgers Coop. Ext.
