Friday, July 13, 2012

Killer pears attacked by Master Gardener

I would like to weigh-in on the debate about the removal of bradford pears in the center of the Village of Yellow Springs.  I appreciate having this blog as a public forum to disperse some information.  In 1982 the bradford pear, Pyrus calleryana Dcne, was voted the second most popular tree by the National Landscape Association. But since then it has moved to the top of the worst tree list in many states including Ohio.  What happened?

This cultivar of bradford pear came from China and was planted as rootstock for cultivated pears in the early 1900’s.  Since it was not self-pollinating, it produced no fruit.  However, when it was planted near other pear varieties, it eventually cross-pollinated to become a much different tree by producing fruits, thorns, and seeds and by growing taller.  Its spread into natural areas began in Maryland and Pennsylvannia where these hybrids produced small fruits that birds, especially starlings, loved.  The seeds spread by birds sprouted, grew, and quickly began to knock out stands of dogwoods and redbuds.  Instead of growing about 20 feet tall as they did when they didn’t produce fruit, the fertile bradford pear grows up to 60 feet tall and spreads to 30 feet.  The tree lives about 25 years if it survives without splitting in a wind storm which many do.  We are in trouble.

This tree is being declared invasive in southern, eastern, and midwestern states including Ohio. Kathy Smith, Ohio State University Extension forestry specialist in the School of Environment and Natural Resources, said at last year’s the Farm Science Review, "You drive into Columbus during the spring when the pears are blooming and they appear to be everywhere.  Once established, they dominate a site just as most of the invasive species do. There are places in Ohio where there are groves of pear so thick you can't walk through them and each of those plants has the ability to reproduce."

A Southwest Ohio Ohio Department of Natural Resources regional forester describes the trees, “They are colonizing waste areas and open fields, and are very tough to control.  Most of you are eyeing all of the greening bush honeysuckle this time of year.  Look carefully and you will see that callery pear will pop up among the honeysuckle.  Yes, callery pear is out competing exotic bush honeysuckle!”  In addition, the ODNR invasive plant webpage listed it as one of its Invasive Weed of the Month. 

In Yellow Springs, many volunteers have removed invasive garlic mustard and honeysuckle from the Glen. Do we want to add thorny bradford pears to this list? Nick Boutis, Director of the Glen Helen Ecology Institute, is already seeing them in the Glen.  For a change, we have a chance to remove the seed source before the trees overwhelm the Glen and prevent the oaks, maples, and other natives from growing.

In addition to their invasiveness, our village pears are in poor shape, not healthy as some critics claim.  They naturally want to be big and spreading, but to avoid hitting buildings and overhead wires, they have necessarily been pruned into unnatural shapes.  Their roots are not compact enough to fit in the small tree wells so they are heaving the sidewalk to find water and nourishment.  These are not healthy trees.  In addition, the bradford pears are notorious for their tendency to split in storms. We are fortunate that one hasn’t already come down on a car, building, or pedestrian.

In other words, bradford pears are no longer appropriate street trees. For the safety of people doing business in town, for the health of the Glen and other natural areas, and for the enjoyment of seeing trees that look like trees, it’s time to replace the pears when sidewalks are installed and wires buried. I’m confident that a committee of experts who know street trees will choose one or more suitable species that will once again provide us with welcome shade and ample branches for artists to decorate. 

Macy Reynolds
Greene County Master Gardener
Ohio Master Gardener Tree Specialist
YS Tree Committee Secretary


lisargold said...

Macy, thank you so much for helping to educate all of us about this issue. This was most informative.

Maureen Lynch said...

Thanks, Macy, for the factual information we all need. Let's hope the Village Manager and Council will be able to provide for public comments and input on this and other parts of the plan, while still getting the work done this season. For instance, has anyone seen an image of the street lights? I hope they are not some cutesy "olde fashioned" style. That's not Yellow Springs today.

Unknown said...

Thank you Macy Reynolds. It is nice to have a documented, thorough scientific explanation of why these trees must be removed. I don't know what sway it will hold over nostalgia "argument", but I am convinced.

Virgil, thanks for providing this on your blog.

jafabrit said...

I can't say nostalgia played a role in my initial reaction. I was just taken aback by the suddenness of it, and lack of public discussion on a major downtown change, or awareness that the tree was presenting such a problem to our glen. FB has provided a great means to explore the issue from many angles and still remain respectful conversation and has proved to be very helpful.

Christine Roberts said...

Why are you so confident Macy? ..."that a committee of experts who know street trees will choose one or more suitable species that will once again provide us with welcome shade and ample branches for artists to decorate" It was a committee of experts that choose the Bradford Pear! When Allentown PA removed 100 of it's Bradfords, they choose another ornamental pear because these trees do well in sidewalks. The new hybrid, Chantileer, however took a weird genetic turn, and it's blossoms smell like dead fish.
As Ohio braces itself for the tremendous loss of all our magnificent Ash trees, I am inclined to applaud the Bradford for its survival spunk! We need another tree that can successfully compete with the honeysuckle in the Glenn. In this age of climate change, global warming and ungodly pollution, we cannot expect to retain our native species.
They are moving north if they are to survive. We need something here that can take the abuse that our truly invasive species, human beings, have created. There is an empty space downtown where one tree has been removed. Lets start there and see what can be planted and how well the new recruit survives.
Sidewalks and trees just do not get along that well with each other. Village council needs to make a commitment to repairing the sidewalks if any tree will be planted. This is the real problem. At this point, after six years of watching our Village Council bungle this maintenance requirement, I am more confident that the Arts Council could repair the sidewalks than I am that the Village Council will ever step up to this duty. Our village government just lacks common craftsman sensibility needed for this and so many other tasks.