Flowering Pear, Callery Pear 'Westwood'

I concluded that this tree is an inferior ornamental long before I found out that it's also commonly invasive.

The lifespa...Read Moren of a callery pear is typically 10-15 years, with luck perhaps 20. (Dirr) I can't count the number of callery pears I've seen split and disintegrate before reaching maturity, because the tree's architecture can't support its own weight, especially in windy, snowy, or icy weather. Since 'Bradford', many cultivars have been released which are claimed to have stronger architecture, but they all have this propensity to splitting, and in the landscape I still see few surviving into maturity.

The flowers are pretty and very early, but they have a powerful pervasive stink.

The foliage is attractive and rarely troubled by disease. Fall color is generally good. But these merits don't begin to make up for the short lifespan.

This tree is tremendously overplanted. Given the variety of beautiful flowering trees that are available, why not choose something with more character and a longer life?

Some cultivars are self-sterile, but they all produce copious viable seeds (bird-dispersed) when they can cross-pollinate with another cultivar, or with root suckers when they're grafted, as they almost always are. The offspring are usually spiny and have become destructive of natural habitat in the eastern, midwestern, and southern US, according to the US National Park Service and the US Fish and Wildlife Service:

http://www.nps.gov/plants/alien/pubs/midatlantic/pyca.htm
http://www.invasive.org/eastern/midatlantic/pyca.html

This species has naturalized from New York to Florida, west to Michigan, Kansas and Texas, and also in Utah and California.