Illegal, invasive Callery pear can be replaced by these trees
Beginning this coming week in Greater Columbus, we should start to see the full bloom of one of the most widely planted flowering trees, the Callery pear. The billowy white flowers of this popular and showy street and landscape tree mask the fact that that this non-native tree is incredibly invasive and aggressive, displacing many native plants that support many beneficial insects and pollinators.
And, as of January, all varieties of Callery pear (Pyrus calleryana) have been added to Ohio’s invasive plant list, making it illegal to sell, plant, grow or cultivate these trees in the Buckeye State. Similar bans have gone into effect in other states including neighboring Pennsylvania.
Removal not required by law
While this new regulation does not
require landowners to remove existing Callery pear trees already growing in the landscape, many environmentally conscious gardeners have begun to remove
these trees from their landscape and are looking for potential replacement trees.
Let’s take a look at some trees with some of the beneficial traits of Callery pear: medium size, white flowers, not favored by insects or disease, native to Ohio, and support beneficial insects, pollinators or wildlife.
Early bloomers
Serviceberry(amelanchier spp.) is an Ohio native with four seasons of landscape interest. You can find Serviceberry in a large multi-stemmed shrub or trained to a small tree with a mature height of 15-25 feet. Like Callery pear, Serviceberry has a showy white flower and blooms early in spring, about the same time that Callery pear is in full bloom.
Serviceberry has excellent fall color with deep shades of gold, red and orange. Varieties that feature stunning fall color include Autumn Blaze, Autumn Sunset and Autumn Brilliance.
Serviceberry flowers develop into plump delicious berries that are a refreshing treat on a warm summer day if you can beat the birds to them. Some Serviceberry cultivars are susceptible to a leaf spot disease that can cause earlyseason leaf drop.
White Eastern Redbud(cercis Canadensis) is the white-flowered version of the more common varieties of Eastern Redbud with pink to purple flowers. Redbuds are a medium-sized tree with a mature height of 15-25 feet and a stately vase shape. The small, pea-like flowers of Redbud bloom just after Serviceberry,
about the time that the first flowering crabapples begin to flower.
Redbuds feature large, heartshaped leaves and seedpods that resemble pea pods. Interesting varieties of the white form of Eastern Redbud include Royal White and Vanilla Twist, which has a weeping growth form.
White Crabapple (Malus spp.) can be a suitable replacement for Callery pear and there are hundreds of varieties to choose from. Crabapple varieties featuring white flowers include Adirondack, Beverly, David and Donald Wyman.
As we discussed recently in this column, when choosing a variety of crabapple, choose varieties that are resistant to apple scab, a leaf disease which causes early season leaf drop.
Mid-season bloomers
Carolina Silverbell (Halesia Carolina) is a small-to-medium-sized tree and an underutilized native tree that features beautiful, showy, bell-shaped white flowers. It has no serious pest issues and prefers slightly acidic soils. This tree does best in moist soils and suffers during periods of drought.
Carolina Silverbell attracts hummingbirds and hosts several species of moth and butterfly caterpillars. Foliage in autumn turns a pedestrian shade of yellow.
Dogwood(cornus spp.) is a delightful four-season tree with its exfoliating bark, brightly colored fruit, and flowers in shades of white, pink, red and yellow. This small tree generally reaches 15 feet tall at maturity. Leaves of Dogwood in autumn turn from scarlet to a red-purple color and the tree produces red fruit that last into autumn and attract wildlife. Cornus kousa is a variety with large, 2-to-5-inch showy white flowers and fruit resembling a round raspberry.
Resist the temptation to plant most Dogwood species in full-sun and highstress locations such as curb strips, as Dogwood does best as an understory tree with some protection from the sun.
Late-season bloomers
Sweet Bay Magnolia (Magnolia virginiana) is a small tree that reaches 1025 feet tall and flowers later in the season. This tree features cup-shaped 2to-3-inch creamy white flowers with 912 petals and a sweet lemon fragrance. This tree prefers acidic soils high in organic matter and, unlike other magnolias, will tolerate heavy clay or wet soils.
While there are no serious insect or disease issues with Sweet Bay Magnolia, this tree can be host to Magnolia scale.
White Fringetree (Chionanthus virginicus), like Serviceberry, can be found as a multi-stemmed shrub or a small tree reaching 15-20 feet tall when mature. This tree features white flowers with slender petals. White Fringetree prefers moist, well-drained soils and will thrive in full sun to partial shade locations.
One caution with this tree is that is has been known to serve as a secondary host for emerald ash borer. While populations of emerald ash borer have been greatly reduced due to the general removal of its primary host from the landscape, the pest is still present in low levels in Ohio.
Mike Hogan is an Extension educator, Agriculture and Natural Resources, and associate professor with Ohio State University Extension. hogan.1@osu.edu