With mounting concern over the warming of our climate and the potential damage of UV rays, the many benefits trees provide are becoming even more valuable. New homeowners are wise to put 'plant trees' high on their 'to-do' list and if possible should try to keep some trees on their property when clearing for construction. With many more, long, hot summers likely in the future, naturally shady areas are bound to become desirable features.
Which trees make the best shade trees? Most people prefer rapid growing trees for quick results, however weak, easily broken limbs are sometimes characteristic of fast growers. 'Moderate' growing trees can still provide relatively quick shade. When you think of maple trees, don't just think of Red or Sugar types. There are striking 'Harlequin ' maples, so popular in the Valley, and ‘Princeton Gold' with yellow foliage.
White Ash (Fraxinus americana) is another large growing tree, with light, lacy foliage. The Eastern Redbud (Cercis canadensis) is an ideal shade tree for smaller areas, growing 7-8 meters tall with a spread of 5-6 m. It has clusters of very showy purple-red flowers before the leaves emerge in early spring. This tree requires pruning, when young, to develop good strong branches and avoid weak forks which commonly lead to early death. Flowering Dogwood (Cornus florida) is another excellent shade tree for limited space, with the same mature dimensions as Redbud and produces white flowers before leaves in spring.
An alternative to growing a small tree for shade is the use of vines. While in PEI many years ago my son and I drawn by the description of one restaurant - "fine country dining beneath a canopy of grape vines.” What a charming place to have lunch on a scorching hot day. Support work in the form of arbors and latticework can be interlaced with living vines like hops, grapes, wisteria or virginia creeper. All are fast growing plants that carry several other attributes besides the production of shade-giving leaves.