''Berberis thunbergii'', the Japanese barberry, Thunberg's barberry, or red barberry, is a

species In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriat ...

flowering plant Flowering plants are plants that bear flowers and fruits, and form the clade Angiospermae (), commonly called angiosperms. The term "angiosperm" is derived from the Greek words ('container, vessel') and ('seed'), and refers to those plants t ...

in the barberry family Berberidaceae,

native Native may refer to: People * Jus soli, citizenship by right of birth * Indigenous peoples, peoples with a set of specific rights based on their historical ties to a particular territory ** Native Americans (disambiguation) In arts and entert ...

to Japan and eastern Asia, though widely naturalized in China and North America, where it has become a problematic invasive in many places, leading to declines in species diversity, increased tick habitat, and soil changes. Growing to tall by broad, it is a small

deciduous In the fields of horticulture and Botany, the term ''deciduous'' () means "falling off at maturity" and "tending to fall off", in reference to trees and shrubs that seasonally shed leaves, usually in the autumn; to the shedding of petals, ...

shrub with green leaves turning red in the autumn, brilliant red fruits in autumn and pale yellow flowers in spring.

Description

''B. thunbergii'' has deeply grooved, brown, spiny branches with a single (occasionally tridentine) spine (actually a highly modified leaf) at each shoot node. The

leaves A leaf ( : leaves) is any of the principal appendages of a vascular plant stem, usually borne laterally aboveground and specialized for photosynthesis. Leaves are collectively called foliage, as in "autumn foliage", while the leaves, st ...

are green to blue-green (reddish or purple in some horticultural variants), very small, spatula to oval shaped, long and broad; they are produced in clusters of 2–6 on a dwarf shoot in the axil of each spine. The

flower A flower, sometimes known as a bloom or blossom, is the reproductive structure found in flowering plants (plants of the division Angiospermae). The biological function of a flower is to facilitate reproduction, usually by providing a mechanis ...

s are pale yellow, diameter, produced in drooping long umbrella-shaped clusters of 2–5; flowering is from mid spring to early summer. The edible fruit is a glossy bright red to orange-red, ovoid

berry A berry is a small, pulpy, and often edible fruit. Typically, berries are juicy, rounded, brightly colored, sweet, sour or tart, and do not have a stone or pit, although many pips or seeds may be present. Common examples are strawberries, rasp ...

long and broad, containing a single

seed A seed is an embryonic plant enclosed in a protective outer covering, along with a food reserve. The formation of the seed is a part of the process of reproduction in seed plants, the spermatophytes, including the gymnosperm and angiosper ...

. They mature during late summer and fall and persist through the winter.

Identification

This species is sometimes confused with '' Berberis canadensis'' (American barberry), ''

Berberis vulgaris ''Berberis vulgaris'', also known as common barberry, European barberry or simply barberry, is a shrub in the genus ''Berberis'' native to the Old World. It produces edible but sharply acidic berries, which people in many countries eat as a tar ...

'' (common or European barberry), and other deciduous ''Berberis'' species; it is most readily distinguished by the flowers being produced in

umbel In botany, an umbel is an inflorescence that consists of a number of short flower stalks (called pedicels) that spread from a common point, somewhat like umbrella ribs. The word was coined in botanical usage in the 1590s, from Latin ''umbella'' "p ...

s, not

raceme A raceme ( or ) or racemoid is an unbranched, indeterminate type of inflorescence bearing flowers having short floral stalks along the shoots that bear the flowers. The oldest flowers grow close to the base and new flowers are produced as the s ...

Cultivation

''Berberis thunbergii'' is widely grown as an

ornamental plant Ornamental plants or garden plants are plants that are primarily grown for their beauty but also for qualities such as scent or how they shape physical space. Many flowering plants and garden varieties tend to be specially bred cultivars that ...

, both in Japan and elsewhere in the

temperate In geography, the temperate climates of Earth occur in the middle latitudes (23.5° to 66.5° N/S of Equator), which span between the tropics and the polar regions of Earth. These zones generally have wider temperature ranges throughout ...

Northern Hemisphere. Numerous cultivars have been selected, including plants selected for yellow, dark red to violet, or

variegated Variegation is the appearance of differently coloured zones in the leaves and sometimes the stems and fruit of plants. Species with variegated individuals are sometimes found in the understory of tropical rainforests, and this habitat is the s ...

foliage, erect growth (for

hedge A hedge or hedgerow is a line of closely spaced shrubs and sometimes trees, planted and trained to form a barrier or to mark the boundary of an area, such as between neighbouring properties. Hedges that are used to separate a road from adjoin ...

use), and dwarf size. In cultivation in the UK, the following have gained the

Royal Horticultural Society The Royal Horticultural Society (RHS), founded in 1804 as the Horticultural Society of London, is the UK's leading gardening charity. The RHS promotes horticulture through its five gardens at Wisley (Surrey), Hyde Hall (Essex), Harlow Carr (Nor ...

's Award of Garden Merit: *''B. thunbergii'' 'Fireball' *''B. thunbergii'' 'Maria' *''B. thunbergii'' f. ''atropurpurea'' 'Admiration' *''B. thunbergii'' f. ''atropurpurea'' 'Atropurpurea Nana' *''B. thunbergii'' f. ''atropurpurea'' 'Concorde' *''B. thunbergii'' f. ''atropurpurea'' 'Dart's Red Lady' *''B. thunbergii'' f. ''atropurpurea'' 'Golden Ring' *''B. thunbergii'' f. ''atropurpurea'' 'Harlequin' *''B. thunbergii'' f. ''atropurpurea'' 'Rose Glow'

Invasive species

Berberis thunbergii flowers in Pennwood State Park

Japanese barberry can be found in most northeastern and

Great Lakes The Great Lakes, also called the Great Lakes of North America, are a series of large interconnected freshwater lakes in the mid-east region of North America that connect to the Atlantic Ocean via the Saint Lawrence River. There are five lak ...

states of the United States. A current map of its distribution can be found at the Early Detection and Distribution Mapping System (EDDmapS).EDDMapS. 2019. Early Detection & Distribution Mapping System. The University of Georgia - Center for Invasive Species and Ecosystem Health. Available online a
"http://www.eddmaps.org/"
last accessed 27 October 2019. In recent years, ''Berberis thunbergii'' has been recognized as an invasive species in many parts of the eastern United States. The Plant Conservation Alliance's Alien Plant Working Group lists it among its "Least Wanted". Japanese barberry is prohibited from being a seed contaminant in

Michigan Michigan () is a U.S. state, state in the Great Lakes region, Great Lakes region of the Upper Midwest, upper Midwestern United States. With a population of nearly 10.12 million and an area of nearly , Michigan is the List of U.S. states and ...

and banned from sale in

Massachusetts Massachusetts (Massachusett: ''Muhsachuweesut Massachusett_writing_systems.html" ;"title="nowiki/> məhswatʃəwiːsət.html" ;"title="Massachusett writing systems">məhswatʃəwiːsət">Massachusett writing systems">məhswatʃəwiːsət'' En ...

. This species is ranked "Very High" on the New York State Threat Assessment scale. This ''Berberis'' is avoided by deer, and has been replacing native species. Furthermore, the plant can raise the pH of the soil and affect soil nitrogen levels. Unlike ''B. canadensis'' and ''B. vulgaris'', ''B. thunbergii'' does not act as a host for ''

Puccinia graminis Stem rust, also known as cereal rust, black rust, red rust or red dust, is caused by the fungus ''Puccinia graminis'', which causes significant disease in cereal crops. Crop species that are affected by the disease include bread wheat, durum ...

'' (black rust), a rust pathogen of

wheat Wheat is a grass widely cultivated for its seed, a cereal grain that is a worldwide staple food. The many species of wheat together make up the genus ''Triticum'' ; the most widely grown is common wheat (''T. aestivum''). The archaeologi ...

. ''B. thunbergii,'' however, naturally hybridizes with ''B. vulgaris,'' and the offspring can be susceptible to ''P. graminis''. Japanese barberry provides an exceptionally favorable environment for ticks due to the high humidity present in barberry's dense foliage. It is hypothesized that spread of barberry is correlated with the spread of

Lyme disease Lyme disease, also known as Lyme borreliosis, is a vector-borne disease caused by the ''Borrelia'' bacterium, which is spread by ticks in the genus ''Ixodes''. The most common sign of infection is an expanding red rash, known as erythema migran ...

. Tick numbers are higher in areas with thick barberry understories, as opposed to areas with controlled barberry or no barberry. In one study, in a barberry infected area, while only in otherwise similar area with no barberry present. Detailed information on how to control Japanese barberry is available in a Michigan Department of Natural Resources document.

Gallery

Image:Berberis thunbergii.jpg, Cultivar 'Aurea' Image:Berberis thunbergii `Atropurpureum`.jpg, Cultivar 'Atropurpurea' File:Berberis thunbergii in Pennwood State Park.jpg, Naturalized ''Berberis thunbergii'' in Penwood State Park in

Connecticut Connecticut () is the southernmost state in the New England region of the Northeastern United States. It is bordered by Rhode Island to the east, Massachusetts to the north, New York to the west, and Long Island Sound to the south. Its capita ...

Berberis thunbergii (2).JPG, Leaves Berberis thunbergii (3).JPG, Leaf

References

External links

US National Park Service: ''Berberis thunbergii''
(deals with the species as an invasive species)
Native Wildlife Garden
(concerning lyme disease in relation to barberry stands)
Species Profile - Japanese Barberry (''Berberis thunbergii'').
National Invasive Species Information Center,

United States National Agricultural Library The United States National Agricultural Library (NAL) is one of the world's largest agricultural research libraries, and serves as a national library of the United States and as the library of the United States Department of Agriculture. Located ...

.
Invasive Species—Best Control Practices, Japanese barberry
Michigan Department of Natural Resources. {{Taxonbar, from=Q158397 thunbergii Flora of China Flora of Japan Plants described in 1821 Taxa named by Karl Maximovich