Scientific Name
Pyrus calleryana ‘Redspire’
Redspire callery pear is a tree native to China and Korea that was originally exploited to breed resistance to the bacterial disease fire blight into more valuable orchard pear varieties. An early breed of the species bred to be thorn-free, ‘Bradford,’ later became a popular fast-growing landscape tree that held a compact shape as it grew to a typical mature height of 35 feet. The tree is very tolerant of drought, pollution and numerous soil types. The ornamental qualities of callery pear are significant, beginning with the often-profuse white flowers toward the end of May, though their smell may not be to everyone’s liking. The foliage is attractive, leathery and glossy and subject to few diseases. In late fall the leaves usually turn bright colors that can range from yellow to red to purple, often all at the same time.
The fruit of the callery pear tree is clearly pear-like, but on a miniature scale (3/8 inches in diameter at most), and has a finely speckled brown exterior like the full-size ‘Bosc’ types sold in markets. The fruits are hard until freezing temperatures soften them, at which time the birds gladly eat them, later spreading the seeds in their droppings. In regions with warmer and wetter climates than here, this has caused this species to join invasive plant lists. Even worse, volunteer trees from open-pollinated seeds often revert to the original thorny nature of the original species. The original breeds of callery pear, especially ‘Bradford,’ proved to be rather short-lived and prone to limb breakage, but newer ones such as the narrow form ‘Redspire’ at Regis are far superior. So far, the improved callery pear breeds have not appeared to be an invasive menace in the Colorado region.