I have a yew in my shade garden. Shrub was planted last spring and didn’t grow much last summer. This year it has put out a lot of new growth and still is, but the middle is turning brown and dropping yellow needles. Is this normal?
From the photograph, your yew looks healthy. The yellowing and shedding of its interior needles while the tips remain green may be caused by senescence, or winter damage.
Senescence simply means getting old, and leaf drop due to senescence is normal. Yews typically drop their old needles in late spring to early summer. Did the 3-5 year old needles on your yew shrub turn yellow, then fall off after a few weeks? If so then it is due to senescence and you do not need to worry.
However, if some of the needles that turned yellow and died are younger, then the more likely culprit is winter damage. Cold winds in winter dry out the needles yet the shrub would have difficulty replenishing itself because the ground is frozen. Sometimes permanent dessication and death of the needles occur. Damage from winter kill may not become evident until later. You can try protecting your yew from prevailing winds with physical barriers, and make sure to water it right up until freezing.
For now, it looks like everything is fine.