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Question from Mike, (received 4/30/20) -

I have a blue spruce approximately 30 feet tall that is losing its color and drying at the top. What could be the problem?

Answer from Dr. Mike Kuhns, USU Extension Forester and Professor (sent 5/1/20) -

Mike,

This tree does not look very healthy, even where the foliage is not turning brown. It has been growing slowly (2-3” a year at the branch tips that are not being shaded by branches and needles higher up, versus 8-12” a year that a healthy spruce should be growing). It looks to me like it was doing well for quite a few years, and then the growth slowed for while – maybe for the last 15 years or so. I base this on the canopy shape (look at the photo with the redbud tree in it) where earlier in its life the tree was growing faster and the canopy was more upright and steep sided, while more recently, shown by the upper part of the canopy, the shape has been flattened, indicating slower growth.

The first and second pictures also look like there are several trees that are planted too close together. They are competing for light, which makes them lose their inside needles and branches. That is a natural thing, but if they are very close together none of them will get enough light. Trees that are too close together will compete for water as well. I think that lack of water is the main thing, though the brown part of the canopy could be a bark beetle attack brought on by water stress.

It won‘t be easy to get to, but the branches or the part of the trunk that are/is turning brown is the place that you would find bark beetles if they are there. There would be insect entry and exit holes through the bark and resin coming out in that area. In the mean time, though, I think that the tree needs more water in the summer and you should consider removing the least healthy trees that are competing the most with others.

Good luck.