Callery Pear | Nebraska Invasive Species Council

Credit: Ansel Oommen, Bugwood.org

General Information

Species Name: Pyrus calleryana

Also Known As: Bradford pear, ornamental pear

Family: Rosaceae (Rose)

Growth Form: Tree

Life Span: Perennial

Flowering Dates:

Origin: China, Japan, Korea, Taiwan

Toxic: Yes, the fruit contains cyanogenic glycosides, which can be turned into cyanide by stomach acids in humans and animals if ingested in large quantities.

Noxious: No

Watchlist: No

Why Is It Invasive?

Callery pear is a rapid-growing tree that poses a major threat to native grasslands and their wildlife. It can quickly fill in gaps in open spaces, which leads to native plants being crowded out as they cannot compete for resources. Birds are attracted to the fruits once they are soft enough to eat, and often they can be hosts for other problematic species like European starlings.

What Does It Look Like?

General Characteristics

A small deciduous tree, it can grow up to 60 feet in height and 2 feet in diameter, though that size is rare. Callery pear trees grow quickly, and typically don’t have time to develop strong structure. They are often susceptible to ice and storm damage and split easily.

Flowers

White flowers are densely clustered with five petals. The blooms typically have a strong, unpleasant aroma, often likened to rotting fish.

Leaves

Leaves are arranged alternately and have a rounded shape. The margin is finely serrated with a distinctly wavy texture. The top of the leaf is a dark, rich green.

Stems

Trees have large egg-shaped terminal buds which are covered in light brown, woolly hairs. The twig is stout and red brown in color. Bark is smooth and covered with lenticels when young, maturing with scaly ridges and shallow furrows in a scaled pattern. Though bred to be spineless, some individuals have sturdy spines.

Seeds and Fruit

Tiny, hard pears appear in the fall. They are brown and almost woody until frost softens them, after which they are readily eaten by birds.

Photos

A callery pear tree with its visible green foliage near some dried grasses and cedar trees in a wooded area

Credit: Ryan Armbrust, Kansas Forest Service, Bugwood.org

Fruit on the branch of a callery pear tree

Credit: Ryan Armbrust, Kansas Forest Service, Bugwood.org

A closeup of the dark green surface on the top of callery pear tree leaves

Credit: Ryan Armbrust, Kansas Forest Service, Bugwood.org

A closeup of the thorny twigs on a callery pear tree

Credit: John D. Byrd, Mississippi State University, Bugwood.org

A closeup of the five-petaled white flower clusters on a callery pear tree

Credit: T. Davis Sydnor, The Ohio State University, Bugwood.org

A closeup of the buds on a callery pear tree's twig

Credit: T. Davis Sydnor, The Ohio State University, Bugwood.org

A closeup of the trunk of a callery pear tree

Credit: T. Davis Sydnor, The Ohio State University, Bugwood.org

A callery pear tree in bloom with its white flower clusters as seen surrounded by other woodland plant species in an open wooded area

Credit: Richard Gardner, Bugwood.org

A closeup of a fruit cluster on a callery pear tree

Credit: Leslie J. Mehrhoff, University of Connecticut, Bugwood.org

A cluster of callery pear trees in bloom with white flowers in an open wooded area

Credit: Leslie J. Mehrhoff, University of Connecticut, Bugwood.org

A callery pear tree with red leaves as it reaches dormancy

Credit: Leslie J. Mehrhoff, University of Connecticut, Bugwood.org

An aerial view of blooming callery pear trees along a street

Credit: Leslie J. Mehrhoff, University of Connecticut, Bugwood.org

Where Does It Grow?

Callery pear is found in a variety of habitats. They are commonly found along roadsides and in old fields, hedge rows or forest edges, but have also been found in wetlands and forests. These trees prefer full sun but also can be found in partially shaded habitat. Because of their tolerance in a variety of soil types, soil acidity, pollution, and drainage levels, they can be a popular urban tree.

How Does It Spread?

Callery pear is a common ornamental and landscape species. It was originally introduced in Maryland in the early 1900s to act as a source of rootstock for domestic pear trees, to help issues with fire blight. Originally, callery pear cultivars had been bred to produce sterile fruit. On the landscape, cross-pollination between species occurred, which led to fertile fruit development. The wild individuals then can interbreed and produce even more viable seed. The most well-known cultivar is the Bradford pear. Callery pear produce a large amount of fruit, which is readily eaten by birds once the pears soften after the first frost. Seeds are then dispersed widely by the birds’ droppings. Callery pear can also spread vegetatively, sending up new shoots from shallow root systems.

How Do I Control It?

Mechanical

Contact your county weed control authority to determine appropriate removal methods.

Cultural

Do not plant callery pear trees as an ornamental and eradicate existing plants on your property. Small callery pear trees may be pulled by hand, being careful to get all the roots. Even small portions of root fragments often resprout.

One way that invasive plant seeds and fragments can spread is in soil. Sometimes plants are planted purposefully. You can prevent the spread of invasive plants.

PlayCleanGo: Stop Invasive Species in Your Tracks