Answer: The definition of a small tree can include those up to about 30 feet tall, so small is a relative word. When you select a tree, you need to check the mature size of it for both height and width -- some are tall and very rounded, some are more columnar. There is a huge range of mature sizes among crabapple varieties for instance, some mature at twelve feet tall, some varieties grow to forty feet. Some smaller trees to consider could include serviceberry, many of the crabapples, the redbud, the kousa dogwood, and some of the deciduous magnolias,for example. Your local county extension should be able to help you analyze the growing conditions where you want to plant and identify small trees (or possibly large shrubs) that would grow well in that spot and mature to be an acceptable size. I hope this helps you get started in your research.
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