If you live in New Jersey, you have likely seen beautiful white flowering trees along roadsides in the spring. You have probably also seen branches from these trees fall off during storms, or smelled their unpleasant odor as you walk by a group of them. Pyrus calleryana, commonly called Callery or Bradford Pear, has quickly become a nightmare tree across many parts of the Eastern United States. What’s so bad about these trees? Read on to find out!
Callery pears are originally from China and Vietnam, and were first introduced to the US in the 1900’s to try and help develop a resistance to fire blight, a disease that was plaguing commercial pear trees. In the 1960’s, they exploded in popularity as a great option for an ornamental tree, particularly the ‘Bradford’ cultivar. The trees were adaptable to many different growing conditions, did well being transplanted, were fairly disease resistant, and produced beautiful flowers without any messy fruit. Many people, botanists included, viewed it as the ‘perfect tree’, and it was planted along streets and in yards across the Eastern US. As the Callery pear became more and more popular, its issues became glaringly obvious.
In the US, the Callery pear is considered an invasive species. The features that had originally made the tree so attractive – adaptability to a wide variety of conditions, resistance to disease, no natural predators in the US – are what enable it to spread rapidly. Individual cultivars of Callery pear will produce fertile seeds if a different cultivar is planted within several hundred feet, which was quite a common occurrence as several different cultivars were developed for particular features. These seeds are then dispersed by birds, and each resulting tree is genetically unique, able to reproduce with other genetically unique pear trees. This has led to fields and streetsides full of Callery pears which, while pretty for a few weeks in the spring, are crowding out native species and reducing biodiversity. Oh, and the wild pears often have thorns, making them extra irritating to remove.
On top of spreading like wildfire, Callery pears and their many cultivars are not-so-great trees for other reasons, too. They are notorious for losing limbs during storms, as they have a poor branching structure. The trees are often composed of many vertical limbs that have weak unions, and the fast growth rate of Callery pears leads to weak wood. The limbs are often unable to support their own weight, and end up splitting off from the main trunk during ice storms and high wind. This is especially troublesome as many pears are planted in yards and along roadways, posing risks to houses, vehicles, and power lines. In addition to their tendency to fall, the flowers on these trees emit an odor not unlike rotting fish for a few weeks each spring. Lovely!
If you ever receive a tree from the NJ Tree Foundation, it will not be a Callery pear or any of its many cultivars. If you’re looking for an ornamental tree to plant in your yard, there are plenty of beautiful native options that fit the bill and do not come with all the issues that Callery pears do. Some of these options include serviceberries, crabapples, and flowering dogwoods. Callery pears are already running rampant in New Jersey – together we can make sure it does not get worse!
