Small trees are the same size as many large shrubs and often can be used for shrub borders and underplantings. Certain varieties of crab apple, cherry, magnolia, dogwood and amalanchier can easily be kept below 15 or 20 feet tall. They are inclined to have a central trunk, rather than a full, bushy habit. They can be trained, however, to grow as multi-stemmed shrubs by pruning them at the ground when they are young and allowing many suckers to grow rather than pruning to a single stem.
Small trees can be trained to grow close to the ground by a technique exactly opposite the one used to prune tall shade trees. For a low profile, the highest growing tip is cut out each year. The lower branches are not removed but instead are cut back (headed back) if they get too long. The lower limbs will absorb more food and increase in size faster. The top will have a tendency to side branch. This technique is practiced in its most sophisticated fashion in espalier fruit trees.