The Garden Shed

Callery Pears are technically varieties of the genus and species Pyrus calleryana. Bradford pear was the first and oldest variety. There are many more varieties of these ornamental pears called; Redspire, Autumnblaze, Cleveland Select, Chanticleer, Whitehouse, Trinity, Aristocrat and many more. Each of these pears has slightly different and in most cases better tree foliage and flower characteristics than Bradford.
Ornamental pears are probably overplanted as a street and shade tree. Because many varieties are planted close together they have crosspollinated and produce many small fruit. When Bradford was only planted, pollination was more difficult and few fruit were produced. These small fruit with many seeds have been widely distributed by birds and others. Many of these seeds germinate and have produced wild ornamental pear seedlings. Thus ornamental pears have become invasive because of the abundance of thees seedlings and the overplanting of these beautiful trees..