Posted: March 29, 2024
Bradford Pear trees have been a common landscape and street tree choice for decades, but they offer few ecological benefits and can even be detrimental to a healthy ecosystem.
Bradford pears were a common street tree choice for decades, but their poor branch angles and tendency to produce water shoots and suckers make them a poor choice, among many other reasons. Photo by Lyndsay Feather.
It's a beautiful spring day – it's finally warmed up again after a week of chilly temps and snow! You step out your front door to go for a walk, take a deep breath in, and smell… rancid fish?! Unmentionable bodily fluids? There must be some roadkill that is wafting by on a breeze… right? Puzzled, you look up and see a tree with cute white flowers blooming in your neighbor's yard – a Bradford Pear tree. That, my friend, is the assaulter of your nasal passageways. Its terrible smell, though, is the least of the environmental and cultural concerns with this all-too-common street and landscaping tree.
Pyrus calleryana, commonly known as Callery pear or its most popular cultivar Bradford pear, is in full bloom across Beaver County. While at first glance these early bloomers with delicate white flowers might not seem different from other spring trees, they have been wreaking havoc on our native ecosystems since the 1960s.
Callery pears were originally brought to the United States from Asia in 1918 as rootstock for domesticated pear fruit trees. However, the Bradford pear cultivar quickly became a go-to street tree choice for city planners across the East and Midwest during the mid-20th century because of their quick growth habit, tolerance of poor soil, small size (rarely over 40 feet), and roots that didn't buckle pavement or sidewalks. Homeowners and landscapers also began using them because of their multi-season visual interest – spring blossoms, dark green summer foliage, and deep red autumn color.
The trees were originally sterile, but over time, Bradford pears cross-pollinated with other non-sterile Callery pear varieties to hybridize and create genetically viable seeds within its small, nutrition-poor fruits. Birds and other critters who eat the fruit drop the seeds in our forests and along roadsides and railways. These seeds grow quickly, and because the trees also spread vegetatively by sending up shoots from shallow root systems, they often create dense thickets and choke out native plants.
Bradford pears are thus "escaping" from the controlled landscape into the wild and are spreading rapidly — outcompeting more ecologically beneficial native plants. Not only are Bradford pears wreaking havoc in the wild, but they are not as wonderful a landscape plant as originally believed.
They can develop sharp thorns along their branches, making them difficult to manage. Their growth habit involves crowded over-branching, making them difficult to prune properly, and they are prone to sending up many vertical "water shoots" when pruned, undoing any attempt at size control. Their branches also grow at narrow angles (more vertical than horizontal), which makes them extremely susceptible to breakage from ice, high winds, and storms. They can be rather paradoxical – while they grow and spread like weeds, they also are rather short-lived, only surviving about 15 to 20 years. On top of all this, their flowers tend to stink like rotting meat!
As their invasive nature has become more and more apparent, there is a growing push in the horticultural community to replace Bradford pears with more ecologically beneficial and native trees. Many states have banned nurseries from selling Bradford pears, and some states such as North and South Carolina, Kansas, and Missouri have run programs to offer free native trees to homeowners who remove Bradford pears from their properties.
Jokes about Bradford pear trees abound: What’s the best way to prune a Bradford pear? One horizontal chainsaw cut, about a foot off the ground! What’s the best use for Bradford pears in the landscape? As firewood! Removing Bradford pears from the landscape and forested areas is indeed crucial to controlling their spread, and the first step is proper identification.
Not every tree with white blossoms in the spring is a Bradford pear – serviceberry trees have white blossoms, and some cherry and crabapples trees do as well. Bradford pear tree leaves are thick, dark green, waxy, and arranged in an alternate pattern. They are rounded with a teardrop shape, are 2 to 3 inches across, and have a very finely serrated margin, or leaf edge. The bark on younger trees is a smooth grayish brown and develops shallow fissures as the tree ages. Flowers of Bradford pears occur in ball-shaped bundles, and half-inch brownish fruits dotted with white flecks develop from these clusters.
You may notice when the trees are flowering that the blooms are buzzing with honeybees and other pollinators. While it's true that Bradford pears can offer an early source of pollen and nectar, there are plenty of alternative tree options that bloom during a similar timeframe that do not pose the same ecological threat as Bradford pears.
Some of the best alternative trees are native serviceberry, including the Allegheny (Amelanchier laevis) and downy (Amelanchier arborea) species, eastern redbud (Cercis canadensis), flowering dogwood (Cornus florida), wild plum (Prunus americana), and many crabapple species (Malus spp.) Many of these trees, including serviceberry, redbud, and dogwood, typically remain rather small and can fill a landscape gap created by removing Bradford pears. All are prolific bloomers and pollinator favorites, playing a crucial role in ecosystem health and diversity, and many have exceptionally beautiful branch architecture, creating visual appeal in the landscape even during the winter.
So, you've properly identified a Bradford pear in your yard, and you've decided that you want to replace it with a beneficial alternative – now what? Depending on the size of the tree you’re dealing with and its location, you may or may not be able to remove it yourself. If the tree exceeds 16 inches in trunk diameter or is near powerlines or a building, you will need to bring in an arborist. Even if the tree doesn’t meet these criteria, you may still want to have an arborist perform the job if you haven’t been trained in chainsaw safety or are otherwise uncomfortable completing the task yourself. You can find certified arborists in our area by visiting www.treesaregood.org.
Once the tree has been cut, it is usually necessary to treat the stump with an herbicide like glyphosate or triclopyr to fully kill it. Remember, Bradford pears are advantageous growers – this is what makes them invasive! The tree will do whatever it takes to survive, including sending up suckers from its root system and causing you more of a headache. Painting cut stumps with an herbicide is an important step – just be sure to read the entire label and follow all directions exactly.
After your Bradford pear is cut and killed, when can you plant your better alternative? The best practice is to wait at least one year after removal to plant a new tree – maybe longer. It’s best to plant 6 to 8 feet away from the old tree, as the old roots take some time to break down. If you need to plant in the exact same spot as the old tree (maybe it's a street tree with limited space between the road and sidewalk), you'll want to grind the stump and wait a couple of years for the roots to decompose sufficiently.
Bradford pears have gotten a bad reputation recently, for good reasons. They cause a myriad of ecological issues and are a poor excuse for a landscape tree, despite any marginal pollinator benefits. Several other early bloomers can brighten up your landscape while also improving ecosystem health and diversity. Please consider removing Bradford pears on your property and replacing them with better alternatives – the birds, bees, and your nose will thank you!
By Lyndsay Feather, Horticulture Educator and Master Gardener Coordinator. This article was originally published in the Over the Garden Gate column of the Beaver County Times on March 27, 2024.
