I apologize that no one has responded to your question sooner. Different experts come online at various times. I just came online and saw your question. My name is ***** ***** I’m a biologist with a special interest in trees. I'm sorry to hear of this problem. I suspect the reason no one replied earlier is that they didn't want to give you bad news. However, I don't want you to think you are being ignored, so I'm going to go ahead and give you some information, even though it isn't what you want to hear. I believe you deserve honesty. These spruce trees are subject to several different fungal diseases that can cause the symptoms you are seeing. Most of them can only be treated with fungicidal sprays.
The one disease that can be treated without spraying is cytospora canker. Along with needles dying, you will have lots of dripping resin from the trees. There will be sunken dark areas on the trunk or branches. Entire branches will turn brown.During wet weather, spores seep out in yellow strings. If this is what your trees have, it is treated with injections of fungicide into the trunk. You didn't mention most of these symptoms, so I doubt your trees have canker.
Your trees most likely have Rhizosphaera needle cast. It has become very common. It's causing a lot of damage on Christmas tree farms. It is controlled there by spraying the trees with Bordeaux mixture or chlorothalonil in early June and again in early July each year. This can control the disease well enough to obtain a harvest of Christmas trees. On trees grown for landscaping, the treatment would have to be continued for the life of the tree. Many homeowners (myself included) have resorted to removing the trees. Without treatment, the trees won't die, but the disease spreads upward. Eventually, there will just be a small amount of green growth at the top of the tree.
You may have heard of the systemic fungicides that are applied in water to the area around the tree. These are great for internal fungal infections, but will not treat those on the needles. You would be wasting your money. If your inability to spray is due to the size of the trees, you might consider hiring an arborist to spray next growing season. In that case, this link will take you to a directory of certified arborists:
Again, I'm sorry not to be able to tell you what you want to hear, but I can't lie to you. spray fungicides are the only way to treat these needle diseases. If you have more questions, let me know in a REPLY. I hope this information at least clarifies things for you.
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