Saturday, March 19, 2016

Bradford Pear, Callery Pear, and Other Cultivars



A cultivar of Callery Pear in bloom.

     This time of year, the presence of Callery Pear becomes quite evident. Overshadowing the magnolias and foreign cherries also in bloom, these invasive plants really dominate the landscape, particularly along edges and old fields. They are quite beautiful actually, despite the flowers' smell that many people dislike. This along with their quick, compact pyramidal growth, "pest free" nature, and tolerance for such a wide array of soil and environmental conditions, made it an extremely popular landscape plant. That it was also self-incompatible, so would not produce messy fruits, was also considered a plus. Callery Pear was originally from China, but has had a landscape presence around here since at least 1960. 

Bradford Pear, a Callery Pear cultivar, with its flowers.

     However, most of these traits also make for an invasive species. This would not have been an issue if they did not reproduce, as was planned, but that particular trait failed. Although the various cultivars, especially the popular Bradford Pear, could not reproduce with their own type of cultivar, so many different cultivars were planted that they indeed do cross pollinate each other. So these have now become an invasive tree species.The Bradford Pear cultivar actually has local ties, being developed in Glen Dale, Maryland as a new wonder tree for landscaping. It was actually the official county tree for Prince George's County until 2009.

Callery Pear fruits and leaves.

Callery Pear escapees invading a forest edge.

     You can really see how invasive they are this time of year when the white blooms make these plants evident all over our countrysides. They are a pioneering species in fields and meadows, sometimes forming monoculture forests. Trying to manage and control their numbers costs natural resource agencies a fortune, but is necessary to preserve habitats. You can do your own part by eliminating seedlings, supporting local management efforts, and of course not planting any of the cultivars of Callery Pear. Be observant next time you're out and see for yourself just how dominant they are.
     There are so many reasons not to plant this tree besides besides their invasive tendencies that out compete native plants and crowd them out. Their pest free nature actually means that they do not support much in the way of native wildlife, no where near what native flora can support. Very few insects such as caterpillars can feed on them (and that means little food for birds, bats, and other wildlife).The woody fruits (pears) are eaten by birds once frost softens them, that is how these are spread. But by my own personal observations, it seems that invasive exotic European Starlings are among the birds who do this the most. They do not provide much food value as native plants, but often are one the few options left. The wood is also fairly weak and prone to breaking and dropping branches. All in all, there are much better native landscaping options available.

6 comments:

  1. Do you have a quick list of web resources on invasive species in VA that you could or have shared on your blog? I want to point some of my well-meaning gardening friends toward more information on invasive as they begin planting this spring.

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  2. Do you have a quick list of web resources on invasive species in VA that you could or have shared on your blog? I want to point some of my well-meaning gardening friends toward more information on invasive as they begin planting this spring.

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  3. The native Serviceberries, Crabapples,and Dogwoods are much better for landscaping in small yards. Lived in Maryland for years and the developers are the ones who planted these everywhere. The main consideration was in all of those awful housing developments what would grow in the clay that was the main soil in the yard after all of the good topsoil was removed? Answer: grass sustained by weed and feed and these godawful Bradford Pears and people still love them. Also, they are considered the U.S. most dangerous tree since so many fallen limbs and split trunks have resulted in injuries to people and property. I replaced mine with American Hornbeam which thrives in clay, sun or shade, and attracts insects and other wildlife all year. Can be made into a hedge also.

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  4. This site is good: http://www.dcr.virginia.gov/natural-heritage/document/nh-invasive-plant-list-2014.pdf

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  5. Also check the Virginia Native Plant Society at www.vnps.org under conservation for their info on various invasive species. Many individual counties and townships have their own lists as well. The MidAtlantic Invasive Plant Council (www.maipc.org) is also a great resource with lots of profiles on certain plants, which states are having issues with them, and links to places.

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  6. Nobody seems to care that these frees were developed with your tax dollars. With a deficit of more than 20 trillion that our children will have to pay, doesn't the nation have more important things to spend our money on than not enough flowering trees?

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