Missouri Invasive Plant Task Force (MoIP) - to identify and control the invasive plant species that severely impact native biodiversity

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What to Do with Your Callery Pears During Quarantine

by Tina Casagrand
What to Do with Your Callery Pears During Quarantine
Use flagging tape to mark your Callery pear trees while in bloom when they are easiest to identify. You can return to the tree and treat it when you are ready. Photo by Felicia Amman.

Our Callery Pear Buy-back events, both scheduled for April in St. Louis and Columbia, have been postponed indefinitely. However, we still encourage property owners to cut the trees during spring (when they are easy to identify) as a means to reducing populations from spreading.

Thank you for doing your part to help slow the spread of this invasive species!

As you remove Callery pear and other invasive plants, please send us a photo to [email protected] or mention us on Twitter and Facebook @moinvasives.

Here’s a quick overview on:

  • how to control Callery pears on your property
  • what to do if you currently don’t have the means to remove these invasive trees, and
  • how to spread awareness about invasive plants beyond your backyard.

Callery Pear invading roadside near Highway 50. Photo by Bill Ruppert.

What’s the problem with Callery pears?

Callery pear (Pyrus calleryana) is a popular ornamental tree native to China. Several cultivars of the tree are offered commercially, including ‘Aristocrat’, ‘Autumn Blaze’, ‘Bradford’ (which is the commonly planted “Bradford pear”), ‘Capital’, ‘Cleveland,’ ‘Chanticleer’, ‘Redspire’, and ‘Whitehouse’.

When cultivars in the “Callery pear” family cross-pollinate, their fertile seeds sprout up and aggressively take over areas where they aren’t wanted. Escaped Callery pear can grow densely along roadsides, unmowed fields/meadows, open woods, or any other open areas. Emerging seedlings will require up to 3 years to be noticeable from a distance, and up to 5 years before trees begin to flower. 

We define an invasive plant species as “an aggressive, non-native species whose presence causes or is likely to cause economic harm, environmental harm, or harm to human health.” These species grow and reproduce rapidly. 

MoIP is most concerned with invasive species because of their direct negative impacts. Callery pear, for instance, is costly to remove and devastating to the habitats where they crowd out native vegetation that is nutritious for local wildlife.

We are encouraging property owners to identify the trees during spring (when they are easy to identify) and remove them from your property as a means to prevent populations from spreading.

OK, I see I can help by removing Callery pears from my own property. What’s the best way to do that?

Use flagging tape to mark your Callery pear trees while in bloom when they are easiest to identify. You can return to the tree and treat it when you are ready. Photo by Felicia Amman.

The following advice comes from Dr. Reid Smeda, University of Missouri Extension, for the Missouri Invasive Plant Task Force:

Control of trees is easier when they are small.

Do not mow seedlings or small trees, as single stem trees will re-emerge as multiple stem trees.

To control trees from seedlings to about 6 feet tall, leaves can be treated with some formulation of glyphosate. An effective rate is 2-4 quarts per acre of a concentrated form (not the Ready-To-Use formulation) of glyphosate. If you want to mix only one total gallon of spray solution, add 4-8 ounces of concentrated glyphosate to 1 gallon of water. Mix the herbicide in water and add a small amount of surfactant (0.5% of final volume). Spray the solution on pear leaves and be sure to cover the entire tree. Be careful to avoid spraying adjacent desirable vegetation, because glyphosate can damage that also. Trees can be treated once leaves come out in the spring until leaves turn color in the fall. Damage symptoms are slow to develop (30 days) and complete control of treated plants can take up to 7 months.

An alternative to treating Callery pear leaves is to treat the base of the tree. Optimum timing for this technique is fall through early winter. Pour a small amount of a concentrated form of glyphosate into a small open-mouth jar. Identify a small, 1 inch diameter, disposable paint brush. Add a small amount of food coloring to the jar and stir to dissolve the food coloring (I like red or blue). No surfactant is needed. Using a chain saw or other saw, cut the Callery pear tree down and make the final cut across the base of the trunk until only a short (about 1 inch) stump is visible. Within 20 minutes of the final cut, paint the top of the stump with a thick coating of the red-colored glyphosate. If control is effective, you will not see any shoots come from the base of the stump.

Be sure to wear gloves and all proper protective equipment as described on the glyphosate label.

Let’s help our native trees and get rid of Callery pear!

I don’t have a chainsaw or other control methods available right now. Is there anything I can do now to stop the invasion of Callery pear trees?

Yes! We encourage you to identify the trees in April while they are flowering and mark the tree with flagging tape or another secure, visible marker. You can go back and control the tree whenever you are ready.

Use flagging tape to mark your Callery pear trees while in bloom when they are easiest to identify. You can return to the tree and treat it when you are ready. Photo by Felicia Amman.

Please make sure you are identifying Callery pear properly. Callery pear limbs generally grow vertically, forming a pyramid or egg shape. In early April, very dense clusters of white flowers cover the tree before leaves form. In maturity, they reach heights of 30 to 40 feet.

See below for more information on proper identification:

Where can I get help having my Callery pear professionally removed?

Please refer to the Grow Native! Resource Guide listings for Arborists and Land Care & Landscape Services to find professionals in your area who can assist with tree removal. These companies are on board with the Grow Native! mission to protect and restore biodiversity.

The Missouri Invasive Plant Task Force is housed under the Missouri Prairie Foundation’s Grow Native! program.

How can I spread more awareness about Callery pear?

We all have a role to play in educating the public about invasive species and their impact on the economy and environment in Missouri and other places we love.

  • Plant native Missouri plants on your property. Learn more at GrowNative.org
  • On social media, share your photos of cutting down your own Callery pear with the facts provided above. Please tag us @moinvasives on Twitter and Facebook, and use the hashtag #InvasivePlant so we can share in your successes!
  • Engage your neighbors, local business owners, and other connections in conversation about invasive plants.
  • Ask your political representatives at the state, local and national level to support invasive species control efforts.

Remember, email us at [email protected] with a photo of your Callery pear removal. We will stay in touch with information about future Buy-backs.

Thank you again for doing your part.

 

Plant This, Not That: 10 Native Trees to Plant in Place of Callery Pear

by MoIP 0 Comments
Plant This, Not That: 10 Native Trees to Plant in Place of Callery Pear
Prunus virginiana (chokeberry or chokecherry) is a small, suckering tree or large shrub with attractive white flowers on 3-6″ long clusters in spring. Fruit is red, ripening to purple in fall. Grow as a screen or as an understory planting as it has unusual shade tolerance for a cherry. Learn more and find nurseries, landscape services and more at: http://grownative.org/plant-picker/plant/chokeberry/ Chokeberry photos from Grow Native! and Flickr user Frank D. Lospalluto. Bradford Pear photo from MDC.

“My heart is broken.” A woman dipped her head back and sighed as cars zoomed behind her and freshly cut tree trunks lay bucked up in scattered rows. A long row of Bradford pear trees, a cultivar of Callery pear (Pyrus calleryanna), had bloomed in her Kansas community for years, and now they were gone. “This is the best part of our neighborhood,” she told a news reporter.

It’s easy to see what she loved about Callery pear trees: billions of white flowers put on shows in early spring and waxy red leaves blaze in the fall. As a plus, they grow fast to fill in new developments.

Of course, a closer look reveals many reasons for a neighborhood to cut down all their Callery pears.

For one, Callery pear blossoms smell terrible. Their showiness resembles a vain monarch who’s trying too hard to impress. Even HGTV recommends finding an alternative to Bradford (Callery) pear trees, due in part to the way their branches break easily in wind or ice storms. And of course, there’s the way the cultivars’ cross-breeding causes big problems as an invasive plant.

While we at the Missouri Invasive Plant Task Force call for stopping the sale of invasive plants such as Callery pear, we know many people may ask, “If I cut down my Bradford pear tree, what should I replace it with,” or, “What should I plant instead of a Bradford or Callery Pear?”

Fortunately, many alternatives are available from Grow Native! retailers and wholesalers.

The following are 10 native Missouri trees we recommend planting in place of Callery pear. These species not only challenge Callery pear in springtime beauty and/or fall color, but they also support the local ecosystem by providing food to wildlife that have coevolved with the trees over millennia. You can’t get much better than that.

This list was inspired by the City of Columbia’s “Stop the Spread” campaign to manage the threat of invasive Callery pear tree hybrids.

Learn more about these and other Missouri native plants on the Grow Native! Native Plant Database.

Download our poster set of Native Missouri Trees to Plant Instead of Callery Pear.

1. Viburnum prunifolium (Blackhaw Viburnum)

Viburnum prunifolium (black haw viburnum) have flat heads of white flowers in the spring. Birds eat the purple-black fruit in the fall. The edible fruit tastes like raisins. Grow as a small tree or multi-stemmed shrub. The leaves develop a beautiful red color in fall. Viburnum photos by Fritz Flohr Reynolds and Suzanne Cadwell. Bradford Pear photos by Bruce Henry and MDC.

2. Prunus americana (Wild Plum)

Prunus americana, Wild Plum, can be grown as a single trunk tree or multi-stemmed shrub. The pure white, fragrant flowers are among the first to open in spring. Heavier flowering in sun. Yellow to red, round, edible fruits, 1″ in diameter. Host to Red-spotted Purple Butterfly and many moths. Wild plum photos by Becky Erickson.

3. Ostrya virginiana (Ironwood or Eastern Hophornbeam)


Ostrya virginiana (ironwood or Eastern hop hornbeam), is a tough understory tree with beautiful birch-like leaves, grayish-brown flaky bark, fine-textured drooping branches, and attractive hop-like fruits. Ironwood is considered one of Illinois’ toughest native hardwoods and is not only ornamental but resistant to many disease and insect problems.Ironwood photos from Flickr user Katja Schulz and Missouri Botanical Garden. Bradford pear photos from John Nekola and Flickr user wplynn.

4. Cercis canadensis (Eastern redbud)

Cercis canadensis (Eastern redbud) bears prolific, edible, deep pink flowers in early spring. Red-purple, pea-shaped seed pods follow the flowers. Heart-shaped leaves turn yellow in fall.
Eastern redbud photos from Grow Native! and Flickr user Matthew Beziat. Bradford pear photos by Martin LaBar and Amanda Nichols.

5. Amelanchier arborea (Serviceberry)

Amelanchier arborea (serviceberry) is a tall shrub or small tree bearing clusters of fragrant white flowers in April. Flowers give rise to very flavorful, red to purple-black, berrylike fruits relished by both songbirds and people. This lovely tree has colorful fall foliage in a blend of orange, gold, red and green. Serviceberry photos by Flickr users Dan Mullen and RJ. Bradford pear photos by Martin LaBar and Amanda Nichols.

6. Carpinus caroliniana (American Hornbeam)

Carpinus caroliniana (American Hornbeam) is a small to medium multi-stemmed tree forming wide spreading rounded tops. A subtle beauty often overlooked. Simple toothed leaves are dark green and have variable yellow, orange, red or reddish purple fall color. Beautiful thin, bluish-gray bark that appears to “ripple” as the tree matures. Hence another common name: “Musclewood.” Hornbeam photos by Flickr users Wendy Cutler and Paco Garin. Bradford Pear photos by wplynn and Roger Smith.

7. Cornus florida (Flowering Dogwood)

Cornus florida (flowering dogwood) is a small, low-branched tree with spreading horizontal branches. Distinctive white flowers, 3″ in diameter, bloom mid-April to mid-May. Clusters of glossy red fruit in fall persist into winter and are relished by birds. Consistent deep red fall leaf color. Dogwood photos by Steve Harwood and Plant Image Library. Bradford pear photo courtesy MDC.

8. Nyssa sylvatica (Black Gum)

Nyssa sylvatica (black gum) is one of our most beautiful and underused native trees. Makes an excellent specimen tree, tidy shape. Attractive, glossy, dark green leaves that turn yellow, orange, and scarlet red in fall. Bark is dark gray to almost black, alligator-like patterns when old. Fruit the size of navy beans ripen to a dark blue in fall and are a favorite food to many birds. Host for the black and white Hebrew Moth. Learn more and find nurseries, landscape services and more at Grow Native! Black gum photos from Grow Native! and Flickr user Leonora (Ellie) Enking. Bradford Pear photos by wplynn and Roger Smith.

9. Cladrastis kentukea (Yellowwood)


Cladrastis kentukea (Yellowwood): very underused native that will fool some into thinking it is an exotic beauty! Medium sized tree, good for small areas, rich pea-green compound leaves with soft golden yellow fall color. The breathtaking, fragrant, creamy-white flowers occur in May on pendulous 8-14″ long panicles. Rarely heavily flowers annually, usually alternate flowering. The bark is very smooth and gray.Yellowwood photos from Flickr user Tom Gill and Grow Native! Bradford pear photos from John Nekola and MDC.

10. Prunus virginiana (Chokeberry or Chokecherry)

Prunus virginiana (chokeberry or chokecherry) is a small, suckering tree or large shrub with attractive white flowers on 3-6″ long clusters in spring. Fruit is red, ripening to purple in fall. Grow as a screen or as an understory planting as it has unusual shade tolerance for a cherry.
Chokeberry photos from Grow Native! and Flickr user Frank D. Lospalluto. Bradford Pear photo from MDC.

Did you find this blog post useful? Please share these images on Instagram, share our gallery on Facebook, and encourage your neighbors to replace Bradford pear with native Missouri alternatives!

Requiem for a Bradford Pear

by MoIP 0 Comments

This shows where the Bradford pear limb broke off from the trunk and apparently other limbs broke from the same area previously. South St. Louis, 2017.

originally published in Outdoor Living, Summer 2014

by Margo Farnsworth

I had inherited my much longed for older sister’s bedroom.  It was a garret-like space that opened into our dusty, but neatly arranged attic with oversized attic fan serving as both focal point and cooling system in the early 1960’s. Here too, was the board where my chalk smudged seven-year-old fingers laid out my future farm.  Lots of horses with paddocks to the west of the house and long southern pastures in the fore were carefully drawn.  The front drive would, of course, be Bradford pears lined up two-by-two all the way to the street.

I was raised on a love of Bradford pears.  Originally sent from China to Europe, their snowy spring dresses came to adorn landscapes in all the most fashionable business parks beginning in the ‘50s.  As subdivisions became popular, so too were these orderly, oval-topped sentries planted throughout neighborhood entries and parks alike.  Their march toward omnipresence had begun.  

As time passed, years of dust settled on the chalkboard with the drawing of my farm.  Bradford pears advanced their hold on whole communities as I was building a career and raising a family.  No horticulturalist, I had not studied the darker side of the pernicious pear.  As I grew, those first pears started to disintegrate in storms.  “Break-away” pears we labeled them as we began to recognize they were neither strong nor long-lived, have lives of usually less than 25 years, with their demise commonly arriving after only 15 to 20 years.

Then, Douglas Tallamy added a tombstone for all of the cultivars of the Callery pear including the Bradford, Cleveland and handful of others.  His studies revealed how poor these trees are in hosting food sources for birds and other wildlife. In a talk for the Missouri Prairie Foundation, Tallamy discussed computations that a single family of chickadee babies will devour 9,000 caterpillars on their way to adulthood.  Those caterpillars like oak trees and other natives – Bradford pears, not so much.

As I wrote this article I contemplated the double row of Cleveland pears the former owners planted on my farm with a rueful smile.  They have fire blight and all must be removed.  I cannot blame myself or you for all the lacy ladies, those Bradford pears planted across our country.  We only went where we were led.  But I can pledge a new allegiance to serviceberry, redbuds and other native trees for beauty along my drive and food in the bellies of birds.  And when a grandchild uses my old chalkboard, I’ll teach them well about the shallow pleasures of a pretty face or flower alone.  Our landscape’s beauty is made of more substantial stuff.  

About the writer: Margo Farnsworth is a writer, biomimicry instructor and Fellow for the Biomimicry Institute. She invites readers into nature, offering strategic ways to live with wild neighbors through biomimicry and other practical methods.  Her work has appeared in the book Wildness: Relations of People & Place along with magazines such as The New Territory, EarthLines, TreeHugger and numerous blogs.