Bradford pear trees were intended to be ornamental and sterile; however, they do produce fruit due to cross-pollination by cultivars like the Aristocrat and Respire, which were developed to lessen the structural weaknesses of the original tree. The fruit is round and less than 1 inch in diameter.
As a result of cross-pollination, the Bradford pear seeds spread rapidly via birds, and they grow aggressively, which results in damage to natural habitats. Their branch structure makes them extremely susceptible to damage from winds, snow, ice and falling branches that endanger houses, automobiles and people. For community safety, many localities, such as Baltimore and Boston, are replacing the older variety of Bradford pear trees that line the neighborhood streets.