Recommendations for browning dwarf Alberta Spruce trees?

https://www.bhg.com/gardening/trees-shrubs-vines/trees/is-there-a-way-to-save-my-dwarf-alberta-spruce/

I would take a sample of the soil to a local nursery. They can check to see if there is a supplement that's missing. You could also bring a trimming from good and bad trees to see if bugs are to blame. The amount of water could be too much or too little.

I had some of these once and they died after 2 or 3 years. Don't know where you live but I think southern Illinois is just too hot for them. Most everything grows like weeds here but evergreens are iffy.

There are several possible causes of browning needles on your dwarf Alberta spruce. One is the spruce spider mite. This tiny mite is active during cool fall and spring weather, feeding on needles of the spruce. If you look closely, you may see yellowish stippling on the needles; it results from a toxin injected into the needles from the mites' feeding. If populations are high, you may also see webbing. Often needles turn brown later in summer when temperatures rise. At that point, little can be done for the tree. You can spray with a miticide or horticultural oil when the mites are present in spring or fall to prevent the problem in the future.

I lost 4 dwarf alberta spruce trees. I was told that at least once a week during the spring, summer and fall to give the whole tree a good, hard spray with water. Unfortunately, by the time you see brown on the tree, you've probably lost it. Remove the brown ones and spray down any ones you still have to try to protect them. It will spread. Make sure to start at the top and work your way down giving it a good hard spray to knock the mites off and drown them.