Question
-------------------------If we had the top diseased portion cut out and removed, would the tree live or should we plan on having the whole tree removed?
Followup To
Question -
I have a large cedar in my backyary that appears to be dieing from the top down. The upper branches are devoid of any greenery or what was green is turning brown. The lower limbs are green and look healthy. This is a beautiful tree and I hate to lose it. Can it be saved?
Answer -
Timothy,

It sounds like your tree has a tip borer problem,  The unfortunate news is usually a conifer does not recover and produce new top growth.  

I would contact a certified arborist for confirmation or if it is another problem that is less severe.

Good luck

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Answer
Timothy,

It would never regain its original form.  Conifers just do not have the latent lateral buds like the broad-leafs do.  If you did remove the top you certainly would have a plant with a unique form.  

Good luck

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