Answer: Each year there will be a certain number of needles that drop naturally, (and clipped off prunings that may be stuck in the shrub will yellow), however it should not be noticeable at a casual glance. If your shrub is dropping a large number of needles there may be a pest or disease problem, or a cultural problem. Since yews are usually quite healthy, I would first investigate the growing conditions. A newly planted yew should be watered so that the soil is kept evenly moist yet not soggy. Over or underwatering could cause it to yellow. With an established plant, a change in drainage patterns could cause the plant to become over or underwatered. Excess deicer salt runoff could also cause yellowing, as could accidental contact with lawn or other herbicide or fertilizer on the foliage. Overfertilizing or use of some chemical sprays could also cause yellowing. If you can not think of any physical reason such as these for the yellowing, I would suggest you contact your county extension and consult with them as to the cause of the problem and what steps you can take. Good luck with your yew bush.
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