cedar tree is dying
A number of cedars were cutdown due to beatle kill. In an adjacent row, the nearest tree to remainkmg stumps is showing signs of dying. Question, if it is in fact beatle can anything be done to prevent death? Also, should it be removed to protect the remaining trees?
If it is beatles that are the culprit, then I think the best course of action for your tree is to "Let It Be". Sorry, I couldn't resist.
In all seriousness, the first piece of information that is needed, is what type of cedar is this? It could be western redcedar, Port Orford-cedar, or incense cedar. They look alike and it's hard to tell from your photos...although, in your photo of the base of the tree I see what looks like it could be a Port Orford-cedar cone (small purplish round object on the ground). I've uploaded an image that shows a comparison of these three species' leaves and cones to help you identify which tree you have.
If indeed you have Port Orford-cedar, then I am pretty sure that you have a root disease, Phytophthera lateralis, which kills the tree. The pattern of brown foliage in your photo looks very much like symptoms of Phytophthera lateralis. The disease is transported through soil and water, meaning that it is likely that other trees in the surrounding area will likely get it. Sometimes trees that are infected with this disease are later attacked by cedar bark beetles, so it is easy to be mistaken that beetles are the underlying problem.
Based on a confirmation of your cedar species, then I suggest that you make a plan for eventual replacement of the trees on this site with a different type of tree (Port Orford cedar and others in the genus Chamaecyparis are the only ones susceptible to Phytophthera lateralis). If you have a different kind of cedar then something else is going on, but even so beetles usually are a secondary agent.