What Is The Extent and Consequences of Ligustrum

sinense Invasion

By Alex Neville

Origins

Ligustrum sinense is commonly known as Chinese Privet.

Introduced to the US in 1850

Uses

Ornamental Hedge, Mass Plantings, Single for floral displays

Plant Characteristics

Member of the Olive Family (Oleacea) Flowers in May Fruit is toxic to humans Cause symptoms such as nausea, headache,

abdominal pain, vomiting, diarrhea, weakness, and low blood pressure and body temperature

Floral odors cause respiratory irritation

The Threat

Rapid maturation Prolific seed production Reproduce vegetatively using suckers Can tolerate wide range of light and soil

conditions Quickly invades disturbed habitats

Newly Colonized Areas

The rapid and recent spread in Oklahoma

Expansion

Chinese Privet is thought to have escaped cultivation by the 1930’s

Current Distribution

Effects

Has the ability to out-compete and eventually displace other plant species

Can reduce plant diversity Can therefore reduce the diversity of plant-

dependent species

Specific Cases

According to the U.S. Fish and Wild Life Service Chinese Privet is one of the major factors pushing Schweintz’s Sunflower towards extinction.

Specific Cases

A study done in the UCA Nature Preserve found 19 out of 20 randomly selected 3 m by 3 m plots in the riparian zone contained privet

Specific Cases

Effects of Ligustrum sinense Lour. (Chinese Privet) on Abundance and Diversity of Songbirds and Native Plants in a Southeastern Nature Preserve by Joshua Wilcox and Christopher Beck

“In contrast, abundance and richness of native plants were reduced in high privet-density plots. Our results suggest that removal of privet would improve native plant communities.”

Control

Extremely difficult once privet is established Due to:

– Large seedbank– Seeds are spread by birds– Need to remove underground parts as well

Control

When in small numbers, removal by hand Direct herbicide treatments Basal-bark or cut-surface treatments Must avoid disturbance for a year afterwards, to allows

the herbicide to take out the whole plant Most effective treatment is cutting, then application of

herbicide to the stump Fire is not feasible, since the disturbance it provides

allow for increased invasion by privet.– Do UCA prairie burns aid in expanding privet populations?

Controls

Biological controls Macrophya punctumalbum is a known pest in

Europe Privet is susceptible to Pseudocercospora

ligustri, which causes fungal leaf spot Also vulnerable to common root crown

bacteria, Agrobacterium tume-faciens

Summary

Chinese Privet is a highly invasive exotic species The plant has spread through most of the southeast Consequences of invasion are reduced plant diversity Reduction of privet numbers is essential to maintain

diversity Control of privet populations is very difficult and labor

intensive Best control is cutting the plant, and then applying

herbicide to the stump

Sources

http://www.bioone.org/perlserv/?request=get-document&doi=10.1656%2F1528-7092(2007)6%5B535%3AEOLSLC%5D2.0.CO%3B2&ct=1

http://plants.usda.gov/plantguide/doc/pg_lisi.doc http://www.invasive.org/eastern/species/3035.html http://www.thewildclassroom.com/biodiversity/problemp

lants/species/Chinese%20Privet.htm