Spiraea japonica, Japanese Spirea


Invasive Species: Spiraea japonica, Japanese Spirea

Japanese spirea is a small, deciduous shrub that grows up to 6 ft (1.8 m) tall and invades a variety of habitats throughout the Eastern United States. The alternate leaves are oval to lance shaped, toothed along the margins, and 1 to 3 in. (2.5 to 7.6 cm) long. In late spring, white to pink flowers occur in clusters at the tips of branches. Japanese spirea invades a variety of habitats, including fields, forests, stream banks, and many disturbed areas. Once established, it can form dense stands which displace native vegetation and close open areas. Japanese spirea is native to eastern Asia and was introduced in the United States around 1879 as an ornamental plant.

What are invasive species, and why should we be concerned about them?


Taxonomy: Scientific and Common Names for This Species

Rosales > Rosaceae > Spiraea japonica L. f.

Spiraea japonica – USDA PLANTS Profile

Distribution Maps

Japanese spirea – The reported distribution of this invasive species across the United States (Source: Invasive Plant Atlas of the United States)

Up-to-the-minute distribution maps and why they are important

Reporting This Invasive Species

What is the best way to report the occurrence of an invasive species?

 How to report an invasive species sighting to EDDMapS – Early Detection & Distribution Mapping System

EDDMapS – Report an invasive species to EDDMapS.

County Extension Offices – Find your county Extension office on this map provided by USDA.

How to Identify

This invasive species can be identified by looking for the characteristics described in the following paragraphs.

Shrub

Japanese spirea is a small, deciduous shrub that grows up to 6 ft (1.8 m) tall.

James H. Miller, USDA Forest Service,   bugwood.org James H. Miller, USDA Forest Service,   bugwood.org

Foliage

The alternate leaves are oval to lance shaped, toothed along the margins, and 1 to 3 in. (2.5 to 7.6 cm) long.

James H. Miller, USDA Forest Service,  bugwood.org James H. Miller, USDA Forest Service,  bugwood.org

Flower

In late spring, white to pink flowers occur in clusters at the tips of branches.

UConn Plant Database, bugwood.org Great Smoky Mountains National Park Resource Management Archive, USDI National Park Service, bugwood.org

Fruit

The seeds measure about 0.1 in. (2.5 mm) in length and are in small capsules.

James H. Miller, USDA Forest Service,   bugwood.org Steve Hurst, USDA NRCS PLANTS Database, bugwood.org

Native Species That Resemble Japanese Spirea

 

Spiraea betulifolia, white spiraea – Images at invasive.org

Dave Powell, USDA Forest Service, bugwood.org Dave Powell, USDA Forest Service, bugwood.org

 

Spiraea douglasii, rose spiraea – Images at invasive.org

Linda Wilson, University of Idaho, bugwood.org Dave Powell, USDA Forest Service, bugwood.org

 

Additional Images for Japanese Spirea

Japanese spirea – Images at invasive.org

 

Learning Resources for Japanese Spirea

 

Additional Information, Biology, Control and Management Resources

Control and management recommendations vary according to individual circumstances. Location, habitat, weather, and a variety of other conditions are factors that help determine the best treatment choice. To find the safest and most effective treatment for your situation, consult your state’s land-grant institution. If you will use chemicals as part of the control process, always refer to the product label.

United States Land-Grant University System – Find your Land-Grant University’s College of Agriculture, University Cooperative Extension Service, or other related partner on this map provided by USDA.

Fact Sheet – Pennsylvania Department of Conservation and Natural Resources

Nonnative Invasive Plants of Southern Forests – USDA Forest Service

Plant Invaders of Mid-Atlantic Natural Areas – National Park Service and U.S. Fish and Wildlife Service

Southeast Exotic Pest Plant Council Invasive Plant Manual – Southeast Exotic Pest Plant Council (SE-EPPC)

Weeds Gone Wild: Alien Plant Invaders of Natural Areas – Plant Conservation Alliance

Spiraea japonica – National Park Service

Spiraea japonica – Global Invasive Species Database

Weed of the Week – USDA Forest Service