Bees at the Bee-Bee Tree

Hundreds of saplings may grow under a female tree.

The Korean Evodia is another tree with a checkered history in North America. The Latin name for this tree included on the City Park Tree Guide is given as Evodia danielli but it appears Tetradium danielli  is also used. Other names include Bee tree, Bee-bee tree or bebe tree. Other sources include the name Honey tree and One Hundred Thousand Flower tree. The current USDA map shows it naturalized in Pennsylvania and Ohio, yet many other states are reporting it as having escaped.

Although Pennsylvania has this species on its watch list for invasive potential, at this point it is not known how it might damage the environment. A four-acre patch of escaped trees has been reported in Maryland. A short article published in 2017 gives more information about the nature of this tree and its invasive nature, stating that hundreds of saplings grow under a female tree and it has been seen outcompeting other invasive species such as the tree of heaven and Japanese stilt grass.

First brought to the United States in the early nineteen hundreds, this specimen is native to the Koreas, northwest China and other parts of Asia. Why is it given its various monikers?

A cluster of buds for the Korean evodia or One Hundred Thousand Flower tree.

Although the many small blooms, in clusters that resemble poorly formed cauliflower heads, are rather high up and hard to see, bees swarm these late bloomers. It is the second week in September here in Colorado and the flowers are still blooming. Purportedly female flowers will turn to stunning red seed pods.

Bees on the flowers of the Korean Evodia

This propensity for late blooming makes the tree popular with both bees and possibly beekeepers. Although many sites mention this as a nectar source, the references I found date to the 1970s with few current citations. One website suggests a substance made from the seeds is used as both a cooking and hair oil!

In the 1990s the US Forest Service lamented this tree was not used more often for ornamental purposes and suggested it would be a good street tree. Similar to the Amur cork tree, parts of Korean evodia have been used in Chinese medicine for 2000 years. It has been used to treat arthritis, headaches, gastric upset, and other ailments. Both WebMD and RxList suggest there is not enough evidence to show if any parts of the plant are effective.WebMD includes a number of drugs with which evodia may interact and cautions pregnant and breastfeeding women from using it. Surgical patients should also use caution as it might interfere with blood clotting.

C185 Korean Evodia (Evodia danielii) is either no longer tagged or the tag is nearly impossible to find when the tree is blooming. At the right time of year, though, it is fairly easy to identify by the many bees buzzing around its flowers and its somewhat unusual  shape. If you found the Amur Cork, walk slightly south and west from there. Although not perfectly aligned with Olive Street, you can also start from where Olive Street tees into Jackson and walk west and slightly south across the park to find it. It is near a large evergreen tree.

Korean Evodia in August

















Amur Cork—Landscape Lovely or Harmful Invader?

First brought to the United States in 1856

Amur cork tree

Amur cork  tree (Phellodendron amurenses) is native to China, Korea, and other areas of Asia. It was first brought to the United States in 1856 and grown in the Harvard Botanic gardens as early as 1908. From 1933 it has been reported to have naturalized in New York. Currently it is considered an invasive plant in a number of states. As an invasive plant it crowds out native trees and produces berries which are less nutritious than the nuts of native trees; its berries do not have the same essential fats needed for wildlife to survive through the winter.

Leaves of the Amur cork tree

Some of the sources referenced above speculate that the trees were brought from Asia by railroad workers. The trees’ growth patterns have contributed to its “success” in crowding out native specie. By suppressing the growth of canopy trees, it has become one of the dominate trees in eastern states. Although many states warn against planting Amur cork, others suggest Phellodendron amurenses is a good landscape variety. A few suggest only male trees be considered. This might be a reasonable solution in areas were there are no others, but in areas where the trees have naturalized, the male tree may still fertilize female trees and add to the problem.

Possibly one of the reasons Amur Corks were originally brought to North America is that it is considered to be one of the fifty most important herbs used in Chinese medicine. Some of its compounds have been used to treat meningitis, arthritis, cancers, and diseases of the lungs. The Ainu population of Japan also used parts of this tree as a painkiller.

WebMD mentions most of the uses above. It also states some of the trees’ compounds, such as berberine, might lower blood sugar and LDL cholesterol. At the same time they include warnings about possible harmful effects. There is limited scientific research to support usage.

Other non-medicinal uses have been mentioned; older literature suggests the bark as a substitute for cork.

The corky trunk of the Amur Cork Tree

It may be used for cork in Russia. An oil made from seeds may have insecticidal properties. A yellow dye obtained from inner layers of bark, was used to produce yellow-tinted paper, useful in distinguishing the important of various Chinese documents.

The Amur cork tree (C138) may be found in City Park  where Olive Street intersects with Jackson Street. As can be seen in the photo at the beginning of this post, the tree is almost directly across from Olive Street street.