To me, this is the "exploding pear tree." Look at the way the main branches all radiate (explode) from the same area above the trunk. Actually this growth habit is characteristic of several forms of the species, and you can see it as a feature of many of the trees in Fort Worth, but this tree is particularly eye-catching and I wonder at it often. Nearly spectacular, in Overton Park.
It's a pretty tree, but this species is way overplanted and becoming explosively invasive and a noxious weed in the USA. Callery pear, an Asian native, began to be planted in the USA as an ornamental in the early 50's, and since then hundreds of thousands of individuals have been planted in the eastern states (see notes below).
Guy Nesom, BRIT
November 2007
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Pyrus calleryana Decaisne Callery pear
Native to eastern and southern China and Taiwan.
Commonly called "Bradford pear," but "Bradford" is just one of many cultivar names -- each name referring to a modification of the growth form of this one species.
A great tree for quick but restrained growth (doesn't get very big), deep green and glossy leaves turning beautiful reds and bronze in the fall. The flowers are spectacularly white, but their heavy, unpleasant odor saturates the air. The fruits are tiny little balls, but they're in the same genus as the edible pear (Pyrus communis), and birds eat them and disperse the seeds.
Additional info and photos
* University of Connecticut Horticulture
* Ohio State University Horticultural and Crop Science
* Wikipedia: Callery Pear
* Missouri Plants.com -- Photographs and descriptions of the flowering and non-flowering plants of Missouri (good pics of flowers and flowering trees)
* Virginia Tech Dept. of Forestry
* Vincent, Michael A. 2005. On the spread and current distribution of Pyrus calleryana in the United States. Castanea 70:20-31.
ABSTRACT: Pyrus calleryana, a very commonly planted ornamental tree species, is documented as an escape from cultivation in the District of Columbia and 152 counties or parishes in 25 states, and is reported as new to California, Michigan, Missouri, New Jersey, and West Virginia. Evidence is presented that the species is rapidly becoming invasive in much of its horticultural range in at least the eastern United States. Some of the escaped individuals (from 14 counties or parishes in 11 states) appear to be of hybrid origin, perhaps between callery pear and P. betulifolia or P. bretschneideri. Callery pear often produces thorny thickets as it escapes into marginal and disturbed areas, and appears to be reproducing readily in the wild. "An ill weed groweth fast." -- John Heywood, Proverbs (1546)
"Pyrus calleryana escapes frequently in areas where it has been in cultivation for about 10 years or longer, judging by the sizes of cultivated trees in the areas where escapes were observed. In places where it is cultivated, it escapes freely as its seeds are spread by birds and is found in disturbed areas such as fence rows, fallow fields, weedy ground, and disturbed woodlots. It often forms dense thickets, and these are often thorny, since thornless cultivars appear to retain genes for thorniness that may be expressed as genes recombine in their progeny" (Vincent 2005, p. 25).
