I have a large, globe-shaped yew (about 7 feet tall) that looks great – the foliage is dense on the outside and its needles are a healthy, dark green. However, when I peer inside, the branches are all bare and the only green growth is on the last 5 or 6 inches of the branches. Is this normal?
Many evergreens, including yews (taxus species), junipers, and arborvitae have a “dead zone” or hollow spot in their interior. There are several causes for this lack of foliage on the interior of the plant. First, as evergreens grow, their new growth is mainly on the exterior of the plant. As the exterior of the plant thrives, the center of the plant receives less and less sunlight. The interior branches are shaded out and die off.
A second cause for the “dead zone” is the natural needle shedding of evergreens in the fall. Evergreens lose their oldest needles, those in the center of the plant, in the fall as a protection from having to support too much foliage over the winter. This shedding of older needles is especially apparent on white pine (Pinus strobus) and arborvitae in the late fall.