Are my Pine Trees dying
Our pathologist examined your photos and found no symptoms of disease or insect damage on ;your spruce trees. The causal factors are most likely a combination of environmental factors. For example, the smallest of the three on the distal end of the row is obviously dead. There is no hope for recovery. This could be the result of inadequate soil moisture in the root zone. It appears that the trees are planted on a raised bed, and if the soil in the raised portion is looser and/or of a different consistency, its ability to hold moisture would be less. Given the smaller size of the tree, the roots are not fully developed and are shallower than the roots of the other two trees. There would be lots of competition for any available moisture and the roots of the middle tree are obviously more developed and probably extend into the root zone of the smaller tree.
The dieback of the lower foliage on the larger tree is not uncommon on spruce trees. This phenomenon is largely unexplainable. It is frequently observed on spruce trees and could be the result of a root problem...again most likely environmental rather than pathological.
The best recommendation we can make is to provide the trees with supplemental irrigation in order to ensure that they receive the equivalent of at least one inch of rainwater each week. Younger and establishing trees may need more, so if you replace the dead tree, be sure to provide the replacement with ample water during the first two years of its establishment phase.
Fertilizer is rarely required and can sometimes result in further damage to the trees.