Stinky Trees Equal Stinky Neighborhoods

Callery pear trees line a residential street.
(Photo: Sarah Kent)

Ah, spring! It is finally here – bringing baby animals, bright sunshine and luscious, colorful flowers. Walking along my street I look up at a tall, white-flowering tree, admiring the flowers when suddenly, the wind changes direction and starts to blow toward me. The smell that follows makes me gag. What is this magnificent, beautiful, smelly tree? The common name is Callery pear or Bradford pear (Pyrus calleryana).

Callery pear trees line a residential street.
They may look harmless, but Callery pear trees are an invasive species. (Photo: Sarah Kent)

When I think of pear trees, a Callery pear is not what comes to mind. In fact, they were not originally planted for their fruit, but for their beauty. Picture this: The year is 1965, the U.S. Department of Agriculture is bragging about how their scientists have cultivated the perfect tree from Asia – the Bradford pear. This tree can grow virtually anywhere, even in the poorest of soils. It can be placed in front of homes as a beautiful ornamental tree that doesn’t grow too high, has sturdy branches and grows quickly. Sounds like the perfect tree, right?

The white flowers of a Callery pear tree.
Don’t let the pretty blossoms of Callery pear fool you; these are non-native plants. (Photo: Sarah Kent)

Fast-forward to 10 years later, scientists are realizing the trees are not as strong – some are even breaking in half during storms! The flowers in spring emit a foul-smelling odor similar to rotting fish. The fruits (which are tiny and not practical for human consumption) are loved by birds, who spread them outside of the neighborhoods that they were planted in. Once in the forests, they grow so fast that they outcompete native trees for sunlight and resources and slowly destroy the native biodiversity we already have in place.

Today, these Callery pears are seen as an invasive species, with some cities even placing a bounty on them. These tree programs reward you if you cut one down by giving you a free native tree to replace it. Ohio has placed a ban on buying Callery pears starting in the year 2023. Unfortunately for us, the trees have a high survival rate. Their seeds can germinate after being dormant for a many year period, they have large roots that allow them to regrow after being cut and the birds love their fruit, spreading them into our forests. With climate change, the pear trees are able to survive what would have normally been colder climates.

Photos show how to identify Callery Pear.
Not sure if a tree in your yard is Callery pear? Here are ways to easily identify them. (Image courtesy Ohio Department of Natural Resources Trees of Ohio Field Guide.)

The fight continues, and luckily there are some easy solutions on what you can do to help. If you notice these trees in your neighborhood or in your yard, talk to your neighbors and see if there could be an easy solution to replacing that tree. This is something that can be brought to the attention of local community councils if they are on public land to be taken care of. If you are planning or landscaping your yard, consider buying a native fruit tree. If you buy a native tree, it helps out local pollinators, you get sweet succulent smells from the fruit and flowers and you can go to sleep knowing that you are making a difference for future generations.

Sarah Kent
Outreach Manager, Great Parks Nature Center at The Summit