Answer: Normally we refer to small trees as those less than 25 to 30 feet in height. Many small trees are comparatively very fast growing providing the new landscape with quick shade; yet, many small trees are comparatively short-lived (15-25 years). Here are a few suggestions for you to consider:
Wax Myrtle Myrica cerifera 15-20 ft. x 15-20 ft. -neutral evergreen, fast rate of growth, easy culture--sun or shade, will stand moist or wet areas and salt conditions, may be pruned to form leggy trunks
Cherry Laurel Prunus caroliniana 25 ft. -small upright evergreen, fast growth, fruit attracts birds, easy culture--sun or shade
Eucalyptus, Silver Dollar Tree (Eucalyptus varieties suggested: E. polyantheme, E. cinerea) 15-25 ft., evergreen, attractive silver-gray foliage, upright, graceful form
You might also consider a Magnolia tree or an ornamental (evergreen) pear.
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