Cornus sericea in the EPPO region: addition to the EPPO Alert List
Considering the potential of invasiveness and the limited presence of Cornus sericea in the EPPO region, the Secretariat considered that this species could usefully be added to the EPPO Alert List.
Why: Cornus sericea (Cornaceae) is a deciduous shrub native to North America. The plant has been introduced voluntarily for ornamental purposes (to attract birds and form windbreaks). Within the EPPO region, its distribution is still limited. Because this plant has shown invasive behaviour where it has been introduced elsewhere in the world and is still limited in the EPPO region, it can be considered an emerging invader in Europe.
Geographical distribution
EPPO region: Austria, Belgium, Czech Republic, Estonia, Germany, Ireland, Latvia, Russia, Switzerland, United Kingdom.
North America (native): Canada (Alberta, British Columbia, Manitoba, New Brunswick, Newfoundland, Nova Scotia, Ontario, Prince Edward island, Quebec, Saskatchewan, Yukon), Mexico (Chihuahua, Durango, Nuevo Leon), USA (Alaska, Arizona, California, Colorado, Connecticut, Idaho, Illinois, Indiana, Iowa, Maine, Maryland, Massachusetts, Michigan, Minnesota, Montana, Nebraska, Nevada, New Hampshire, New Jersey, New Mexico, New York, North Dakota, Ohio, Oregon, Pennsylvania, Rhode Island, Utah, South Dakota, Vermont, Virginia, Washington, West Virginia, Wisconsin, Wyoming).
Note: the Native Americans smoke this plant in the sacred pipe ceremony and use it to make dream catchers.
Description
C. sericea is a multi-stemmed shrub growing from 1.4 to 6 m high. The young stems and twigs are dark red, gradually fading to grey-green, and becoming red again in the autumn and winter. The leaves, which are 10 cm long, are opposite with prominent lateral veins, dark green above and hairy and lighter-coloured below. Autumn foliage is colourful. Flowers are 2-3 mm wide, creamy-white, gathered in dense flat-topped clusters. Flowering occurs from June to August. Fruits are white berries gathered in umbrella-shaped clusters.
Biology and ecology
The flowers of C. sericea are self-sterile. Pollinators include bees and possibly beetles, flies, and butterflies. Seeds are dispersed primarily by birds, although other animals including bears, mice, and even trouts may eat the fruits and disperse seeds. Individual plants generally first produce fruits at 3 to 4 years of age, but older plants are more prolific. Seeds have a dormant period and need cold stratification for 1 to 3 months. The seeds remain viable in cold storage for 4 to 8 years. This shrub has also a strong vegetative reproduction capacity. It spreads by layering when the lower stems touch or lie along the ground and root at the nodes.
C. sericea is mostly found on moist soils, where it can live with the roots submerged in water for most of the growing season. It has a wide geographical range and is able to tolerate extremely cold temperatures. It generally grows at elevations below 2500 m.
Habitats (adapted from Corine Land Cover nomenclature)
Inland wetlands: swamps and damp woodlands.
Banks of continental water: riverbanks, lake shores.
Road and rail networks and associated land: railway embankments.
Other artificial surfaces: forest margins, fallow lands.
Impacts
C. sericea can cover large surfaces and produces a dense canopy which reduces the development of native vegetation.
Control
No information available.
Sources
Belgian Biodiversity Platform. http://www.biodiversity.be
Delivering Alien Invasive Species Inventories for Europe (DAISIE). http://www.europe-aliens.org/
NOBANIS - Network on Invasive Alien Species. http://www.nobanis.org/
US Forest Service. http://www.fs.fed.us/database/feis/plants/shrub/corser/all.html
United States Department of Agriculture – Natural Resources Conservation Service. http://plants.usda.gov/plantguide/doc/cs_cose16.doc