Answer: What a perplexing turn of events. I would suspect either something going on underground, or some sort of infection or infestation. We have had a very dry summer, fall and so far winter and a number of established plants are showing problems for that reason. It is also possible that the plants' roots have grown in a circular direction underground (due to improper planting technique or serious potbound condition prior to planting) and are now beginning to strangle themselves. It is also possible that unbeknownst to you, "something has happened" to those plants, perhaps inadvertently due to pets, children, workmen, a neighbor.... With regard to other problems, yews can be attacked by blights, root rots, other assorted fungus and of course, insects. You might wish to consult with a professional arborist and/or with your County Extension (696-3500) to try to determine the cause of the browning.
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