Should Bee-Bee Tree be Avoided?

Contact: Sylvan Kaufman |

Should Bee-Bee Tree be Avoided?
Should Bee-Bee Tree be Avoided?
Photos: Pat Breen, Oregon State University.

ANNAPOLIS, MD (July 01, 2016) – One way to prevent new plant invasions is to be on the lookout for species that seem to be spreading into natural areas a little too aggressively. Which plants will be the next tree of heaven, running bamboo, or kudzu? Marylanders are on the lookout for many invasive species in natural areas, including bee bee tree, or Korean evodia (Tetradium daniellii), an ornamental tree from northern China, Tibet, and Korea. Because this tree is a summer bloomer, MISC has chosen it as the July Invader of the Month.

The first arrival of bee bee tree to the United States was probably in Massachusetts when a plant explorer visiting eastern Asia sent seeds to the Arnold Arboretum in 1905. In the 1920s the United States Agricultural Research Station in Beltsville, MD received seeds from China. Although not widely grown as an ornamental, plants have escaped cultivation in Ohio, Pennsylvania, Missouri, Washington DC, Virginia, and Maryland.

A homeowner near Leitersburg, MD recently reported a four-acre infestation in a forest where the bee bee trees appear to be outcompeting another invasive tree, tree of heaven. She noticed the tree because of the loud buzzing of many bees visiting the flowers.

This medium sized tree produces abundant clusters of small fragrant white flowers in mid to late summer. Honey bees find the flowers very attractive. On female trees clusters of fruits ripen to a red – purple color. Each fruit contains two shiny black seeds. The trees have smooth grey bark at all ages, similar to a beech tree, but the compound leaves are made up of 7 – 11 oblong leaflets arranged opposite each other along the leaf's stem. Amur corktree, a close relative, has similar looking leaves and is also on watch lists of potentially invasive plants.

Staff at the National Arboretum in Washington, DC and the Blandy Arboretum in Boyce, VA report trees spreading into surrounding woodlands and hedgerows from ornamental plantings. You are most likely to find bee bee trees escaping into disturbed forests and forest edges. They prefer to grow in sunny sites, but tolerate partial shade. They will grow in a wide range of soil types but prefer moist, well-drained soils.

Should Bee-Bee Tree be Avoided?
Should Bee-Bee Tree be Avoided?
Photos: Pat Breen, Oregon State University

Land managers are concerned about the escaped plants because they can grow in dense stands and could potentially shade out other tree seedlings and woodland plants. If you find escaped bee bee trees, record the location of the trees and contact the manager of the park or natural area where you discovered it. Maryland's new Statewide Eyes program also allows observers to report newly found invasive plants in natural areas. Visit Maryland DNR's Statewide Eyes page for more information on how to participate.

For more information about other Invasive Species of Concern in Maryland, visit the Maryland Invasive Species Council or call the Maryland Department of Agriculture at 410-841-5920.

photos available electronically on request.

For more information on the Internet:Invasive Plants in Pennsylvania: Bee-Bee Tree, Pennsylvania Department of Conservation and Natural Resources (DCNR).