Did this tree start out as an ornamental tree and change into another?

Question

I found what looks like two trees in one. First there is the weeping ornamental crab apple tree, or other ornamental tree that was planted with another of the same, right beside it. However it also has the appearance of a Bradford Pear tree. A huge branch(es) from the smaller tree has grown into a Bradford Pear. I was wondering how that may happen?

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Answer 1

My guess is that the weeping tree was grafted. This lets the grower have the benefit of a vigorous root system. But, if suckers aren't removed, rootstock growth takes over.