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

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“Plant This, Not That!” Posters Now Available

“Plant This, Not That! Native Missouri Trees to Plant Instead of Invasive Callery/Bradford Pear” is an 11-poster set (title page + 10 species) inspired by the “Stop the Spread” campaign and designed by Missouri Invasive Plant Task Force. Now available in the following formats:

Why Not Callery Pear? Title Poster for “Plant This, Not That!” series

Missouri Noxious Weed Law – Not Right for Callery Pear

 

When the Missouri Department of Conservation posted about stopping the spread of Callery pear, there were several good questions and comments about legal ramifications for distributing invasive plants. We will address some of them here.

 

“If Callery pear trees are a problem, why are they sold at almost all home stores?”

It is not illegal to sell Callery pear. While many small nurseries are aware of the problem and no longer carry Callery cultivars, large stores with national purchasing programs still stock Callery on their sales floor.

The only Missouri law concerning invasive plants is the Noxious Weed Law 263.190, which identifies only 12 species of plants. Most of those species are commonly known to threaten agricultural land.

The Noxious Weed Law comes with two legal mandates:

  • Noxious weeds may not be sold.
  • Landowners must control and/or eradicate these particular weeds.

Since Callery pears are planted on countless lawns and landscapes, the second mandate would require all private homeowners to cut down their pear trees. That would be highly unpopular. Plus, there aren’t enough resources to enforce the law.

Failure to comply with the Noxious Weed Law is a misdemeanor. County prosecutors enforce it.

 

“Ban the things. Other states do. They cannot be shipped there.”

Currently, adding a plant to the Noxious Weed Law list requires review and approval by the Missouri Department of Agriculture.

However, to create a new designation of plants that are banned from sale (and not require landowners to control) would require changing statutes through the legislative process.

The State of Ohio recently passed new legislation that bans the sale of 30+ species of known invasive plants (read law here). Missouri agencies are aware of the legislation. The Missouri Invasive Plant Task Force is currently reviewing the spread of invasive species statewide in order to make research-based recommendations regarding new rules.

 

“Could the USDA be petitioned to stop the sale?”

We prefer to educate the public rather than pursue top-down measures.

 

“What can I do to stop the spread?”

Spread something else: spread the word! Tell the story about how ornamental pears are cross-breeding with cousins, and how it’s becoming a big problem for roadways, empty fields, and other landscapes in Missouri. Contact your city officials, legislators, and governor, to express your thoughts on Callery pear and other invasive species. Advocate for solutions at all levels of your community.

About Noxious Weed Law, from the Missouri Department of Agriculture

The State of Missouri has designated twelve weed species as noxious.

Weeds on this list are designated as such because they can cause economic harm to the state’s agriculture industry and because of the high level of difficulty associated with controlling or eradicating the species. For more information visit Noxious Weed Control (http://agriculture.mo.gov/plants/ipm/noxiousweeds.php)

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

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.

 

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!

What you need to know about Bradford pear trees to keep Missouri ecology healthy

rattlesnake master and blazing star with quote “I will argue that every scrap of biological diversity is priceless, to be learned and cherished, and never to be surrendered without a struggle.”

Photo by Bruce Schuette, Missouri Department of Natural Resources, Missouri State Parks, from the Missouri Invasive Plant Case Study Site Cuivre River State Park.

 

When non-native plants cause significant ecological or environmental harm, we consider them “invasive.”

Invasive species regularly appear in Top-5 lists of the most significant threats to biodiversity, along with habitat loss, climate change and pollution.

In the case of Bradford pear (as it is most popularly called, though we’re really talking about all cultivars of Callery pear–more on that later), its potential harm to ecology and environment is substantial.

Here are some reasons why MoIP is choosing to focus attention on Bradford pear this year:

1. They can displace native plant communities

When thinking about invasive plants from an ecological perspective, the most important aspect is how they displace native plants communities.

Native plant communities are important for a number of reasons. Plants native to a particular area have co-evolved with other plants and animal species that we love and that keep our ecosystems healthy.

Native plants provide food for caterpillars and other insects, that are in turn eaten by larger animals. Non-native plants do not share evolutionary history with other native species, and therefore are not as ecologically beneficial as native counterparts. (For more, read this article by Doug Tallamy.)

Because Bradford pears grow so quickly, they can form thickets in large areas of land just a few years after sprouting. And as with many non-native plants, it leafs out earlier than native species, which shades out spring wildflowers. This alters the natural light and micro-climate of the land around the pear trees. It limits the ability of native plants to re-establish themselves.

And this is important, because as E.O. Wilson says:

“I will argue that every scrap of biological diversity is priceless, to be learned and cherished, and never to be surrendered without a struggle.”

2. Without control, invasive ornamental pear trees are geared up to take over quickly

If different cultivars of Callery pears (including the Bradford pear) are grown in proximity, they can cross-pollinate and produce fertile seeds, carried by birds into new areas.

This fact sheet from the Missouri Department of Conservation says it well:

Callery pear is adapted to a wide variety of environmental conditions, including heavy clay soils, drought, heat and pollution. Growing best in full sun, it also tolerates partial shading. Spreading into open, disturbed habitats, naturalization occurs within early successional fields, parks, rights of way, power lines and other natural open areas. It grows rapidly, flowers at a young age, often develops thorns and produces large amounts of seed. It is also establishing in the understory of forests and woodlands and is able to flower and fruit in small canopy openings.

The seed bank and sprouting ability of Bradford pear persists for years after cutting or treatment, so further management is needed beyond the first treatment.

3. You can do something!

Plant native alternatives. The City of Columbia’s “Stop the Spread!” campaign suggests the following: