Winter’s chill can harm many types of trees, including yews. Contrary to what you might think, winter injury to yews doesn’t generally follow an extremely cold winter. This winter injury occurs after extreme temperature fluctuations rather than prolonged cold weather. Browning of yews may be caused by many other factors as well. Yew winter damage may not be always be caused by fluctuating temperatures but by salt. Yews are sensitive to salt used for deicing roads and sidewalks. If the deicing salts get into the soil under a yew tree, you should flush it out by giving the tree generous amounts of water. Yew trees turning brown is not always a result of winter injury either. Keep reading the tips in the source.