Advice please. I have a 50' blue spruce which has started to die.
The best way to determine what is happening with your spruce is to have a qualified person on site to evaluate the surroundings and the tree and, then, combine that information with knowledge of the weather, both recent and prevailing. Among the persons who can provide knowledgeable opinions are Certified Arborists. Have at least 3 persons visit, compare their opinions and, then, make a decision.
You can locate Certified Arborists if you look in the Yellow Pages, either hardcopy or online under the heading of Tree Care or something similar. Companies with Certified Arborists will state that in their ad. And in some towns and municipalities, the Street Tree Department or the Parks Department assists homeowners.
In the meantime, take a long hard look at your spruce so that you can clearly explain which parts are affected. Interior browning indicates a normal loss of needles or if more marked than usual, a shortage of water. Individual dying branches could be due to insects or disease. And if the spruce is dying from the top down, it may be too late to stop the problem. Unfortunately, not all failing trees can be saved.