• Beth Kilgo

Wolf Creek Trout Lily Preserve: Invasive Species, Part Two

Part two in a three part series on the invasive species in the Wolf Creek Trout Lily Preserve and surrounding areas. part two discusses the Chinese Privet.This series goes with the series on the Preserve.

None of the pictures are owned by the author of the article.

There are several invasive species that threatened the wetlands and the trout lily slope, many of which, known by their common names, aren’t always thought to be invasive. Of those are Japanese honeysuckle, Chinese privet, and the inch plant, all are common names.

The Chinese privet is an aggressive species known for pushing native species to extinction. The Chinese privet is simi-evergreen, and the younger leaves tend to be covered with a thin layer of short hairs.

The privet produces white or cream-colored flowers in April and lasts until June. The flowers form clusters in the crook or tip of branches. The pollen may cause allergic reactions; in addition, the berries formed are poisonous to both people and dogs. The leaves can be more toxic than the berries when in large enough quantities. The symptoms in dogs are rarely fatal; however, vomiting, diarrhea and appetite loss appear after a few berries or leaves have been consumed.

The berries start out green, and then ripen to black, remaining into winter. The berries are one way that the privet spreads. The privet also spreads through root sprouts.

All species of privet are native to Asia, Europe, and North Africa; however, privet has been developed into ornamental varieties and is sold in the United States. When introduced in 1852, the invasive characteristics of the Chinese privet were not known, but it was considered a great landscape plant, as it remains to this day, because of its tolerance to air pollution.

Chinese privet, ligustrum sinense, can grow to be 16 feet tall, and has a smooth texture with tan or grey bark. The leaves are arranged on the thin branches. The flowers, like most flowering plants, have both male and female parts. The berries, called drupes, are oblong, blue, or black in color and contain one-to- four seeds. When mature, the tree can produce hundreds of drupes.

The aggressive nature of the Chinese privet allows it to form dense patches that compete with and run out desirable plants. The number of seeds produced by the shrub allows it to survive and spread despite efforts to remove it. Even though it is an invasive species, landscapers still use it, and garden centers still sell it.


Mowing, cutting, and physical removal of the seedlings are a few matters of management. Preventing the privet from taking root by not planting it and using alternatives that are not invasive or planting native plants are effective. To ensure it doesn’t spread when removed, move it when it isn’t producing seeds. Physical removal requires the entire root system to be removed so that it won’t grow back.