Stinky flowers, weak wood prone to breaking apart, and poor growth form are some of the better-known problems of the callery pear (Pyrus calleryana) tree. Its invasive qualities, though, set it apart as a truly abhorrent selection for planting here in Novi. This exotic species from Asia, which has been widely planted by homeowners and municipalities since the 1960s, is highly adaptable to different soil conditions and its fruit is desirable to birds which allows it to spread far and wide. However, the tree crowds out native trees and shrubs, thus greatly reducing biodiversity and causing ecological harm anywhere it gets established.
The City of Novi has banned the callery pear from use in new development planting plans for years, but this species is still commonly planted by individuals thanks to its widespread availability at nurseries and box stores. In fact, thousands of callery pear trees still grow in Novi today. This is in part because few state governments have cracked down on the species, though that is starting to change. Ohio placed callery pear trees on its invasive species list in 2018, then fully banned their sale in early 2023. Pennsylvania and South Carolina have also passed bans on the species that will go into effect in 2024. Other states—Indiana, Kentucky, and North Carolina—have created “bounty” programs, which offer residents native replacement trees in exchange for the removal of their callery pear trees.
The callery pear is not listed as an invasive species by the State of Michigan, however, and the sale, distribution, and planting of this harmful species continues in the mitten unabated. There are many native species alternates for callery pears. Flowering dogwoods, native hawthorns, and serviceberry all produce similar boastful white blooms, minus the stinky odor. Paradoxically, these beneficial native species tend to be scarce at commercial garden centers. Perhaps retail stock and the consumer market could shift toward more native biodiversity if the State of Michigan follows the lead of our neighbors to the south and bans the sale of callery pear trees.