By Tom Barry
Yews make for an excellent evergreen hedge. Typically, the method for pruning these types of shrubs is to shear them into a neat, manicured hedge. Shearing is a pruning technique where the outermost parts of the plant are cut back to create the formal, hedge appearance. This type of pruning does not follow the natural habit of the plants' growth. Also, this continual type of pruning creates a very dense outer canopy which restricts light from going into the inside of the plant. No light into the center of the plant means no leaves being produced and if you are not cutting enough of the new growth off every year, controlling the size of these shrubs becomes a problem.
At GFA we have had yews around campus that have become staples of the landscape. Many of them have been around for as long as the school has. Unfortunately, these yews have become overgrown for the space they were initially planted in and were growing over walkways and stairs and restricting views. Since they have no internal growth due to the shearing over the years, there is no way to prune them back and maintain their appearance.
To remedy this issue, the GFA Grounds Crew are implementing an aggressive type of pruning known as rejuvenation pruning. This means drastically cutting back an overgrown shrub or hedge, usually to about 18 inches, to reduce its size and approve its overall appearance. Certain shrubs can tolerate this type of pruning better than others. Fortunately, yews are known to be able to recover well however, it usually takes a few seasons.
The most prominent area where this pruning took place was on the front terrace. A very large yew hedge that had become overgrown was blocking the view from the faculty lounge out onto
the front lawn. This hedge was also growing over a walkway and engulfed a staircase railing. We took the hedge down to about 1/3 of its height and we expect to see new growth coming out in the spring. In the process we also exposed a stone walkway which was buried underneath the years of growth of the shrub.
Going forward we will continue to control the size by shearing but also occasionally doing some thinning pruning to allow light to penetrate into the center of the shrub. Although it might be unsightly for a period of time, it is the definition of regenerative landscaping and avoids spending more money on replacing the hedge with new plants. Let's watch as the magic happens and these iconic shrubs “spring” back to life.