''Kerria japonica'', commonly known as Japanese kerria or Japanese rose, is a

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 Leaf, leaves, usually in the autumn; to the shedding of petals, aft ...

, yellow-flowering

shrub A shrub or bush is a small to medium-sized perennial woody plant. Unlike herbaceous plants, shrubs have persistent woody stems above the ground. Shrubs can be either deciduous or evergreen. They are distinguished from trees by their multiple ...

in the rose

family Family (from ) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). It forms the basis for social order. Ideally, families offer predictabili ...

(

Rosaceae Rosaceae (), the rose family, is a family of flowering plants that includes 4,828 known species in 91 genera. The name is derived from the type genus '' Rosa''. The family includes herbs, shrubs, and trees. Most species are deciduous, but som ...

native Native may refer to: People * '' Jus sanguinis'', nationality by blood * '' Jus soli'', nationality by location of birth * Indigenous peoples, peoples with a set of specific rights based on their historical ties to a particular territory ** Nat ...

to China and Japan. It is the only species in the genus ''Kerria''. In the wild, it grows in thickets on mountain slopes. Japanese kerria has been used for medicine and is also planted in gardens. A double-flowered

cultivar A cultivar is a kind of Horticulture, cultivated plant that people have selected for desired phenotypic trait, traits and which retains those traits when Plant propagation, propagated. Methods used to propagate cultivars include division, root a ...

, ''K. japonica'' 'Pleniflora', is commonly called bachelor's buttons. When cultivated in the Central-Southern U.S., the plant is usually called Yellow Rose of Texas. Although genus Kerria is in the rose family, it is not a true rose.

Name

The genus name ''Kerria'' is also a common name for the species (Kerria). It is named after Scottish gardener William Kerr, who introduced the Japanese kerria

'Pleniflora'. In addition to the common names mentioned above, it is also known as Japanese marigold bush or miracle marigold bush in northern

New England New England is a region consisting of six states in the Northeastern United States: Connecticut, Maine, Massachusetts, New Hampshire, Rhode Island, and Vermont. It is bordered by the state of New York (state), New York to the west and by the ...

, although ''K. japonica'' is not closely related to the true marigolds (''

Calendula ''Calendula'' () is a genus of about 15–20 species''Calendula''.
Flora of China.

'' spp.), which are

asterids Asterids are a large clade (monophyly, monophyletic group) of flowering plants, composed of 17 Order_(biology), orders and more than 80,000 species, about a third of the total flowering plant species. The asterids are divided into the unranked cl ...

. It is sometimes known by its Japanese name ''yamabuki'' () lit. "mountain

butterbur ''Petasites'' is a genus of flowering plants in the sunflower family, Asteraceae, that are commonly referred to as butterburs and coltsfoots.

Description

''Kerria japonica'' grows to tall, with weak arching stems often scrambling over other vegetation or rocks. In the wild it grows in thickets on mountain slopes. The

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

are alternate, simple, long, with a doubly serrated margin. The

flower Flowers, also known as blooms and blossoms, are the reproductive structures of flowering plants ( angiosperms). Typically, they are structured in four circular levels, called whorls, around the end of a stalk. These whorls include: calyx, m ...

s are golden yellow, with five

petals Petals are modified leaves that form an inner whorl surrounding the reproductive parts of flowers. They are often brightly coloured or unusually shaped to attract pollinators. All of the petals of a flower are collectively known as the ''coroll ...

, and evenly-spaced along branches of new green growth. The

fruit In botany, a fruit is the seed-bearing structure in flowering plants (angiosperms) that is formed from the ovary after flowering. Fruits are the means by which angiosperms disseminate their seeds. Edible fruits in particular have long propaga ...

is a dry single-

seed In botany, a seed is a plant structure containing an embryo and stored nutrients in a protective coat called a ''testa''. More generally, the term "seed" means anything that can be Sowing, sown, which may include seed and husk or tuber. Seeds ...

achene An achene (; ), also sometimes called akene and occasionally achenium or achenocarp, is a type of simple fruit, simple dry fruits, dry fruit produced by many species of flowering plants. Achenes are monocarpellate (formed from one carpel) and Dehi ...

long.

Cultivation

Kerria is valued in gardens for its golden yellow flowers, which appear in the spring. It is best grown with some shade from full sunlight to avoid blanching the flowers, and needs to be pruned after flowering to maintain health and vigour. Two

cultivars A cultivar is a kind of cultivated plant that people have selected for desired traits and which retains those traits when propagated. Methods used to propagate cultivars include division, root and stem cuttings, offsets, grafting, tissue cult ...

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 ...

Award of Garden Merit The Award of Garden Merit (AGM) is a long-established award for plants by the British Royal Horticultural Society (RHS). It is based on assessment of the plants' performance under UK growing conditions. It includes the full range of cultivated p ...

, ''K. japonica'' 'Golden guinea' and the double-flowered ''K. japonica'' 'Pleniflora', commonly known as bachelor's buttons.

Pests and diseases

Since 2014 the UK's Royal Horticultural Society has been receiving reports from gardeners and horticulturalists of damage to plants of the shrub ''Kerria japonica''. Symptoms include multiple red spots on leaves, and

lesion A lesion is any damage or abnormal change in the tissue of an organism, usually caused by injury or diseases. The term ''Lesion'' is derived from the Latin meaning "injury". Lesions may occur in both plants and animals. Types There is no de ...

s on the stems, resulting in

defoliation A defoliant is any Herbicide, herbicidal chemical sprayed or dusted on plants to cause their Leaf, leaves to fall off. Defoliants are widely used for the selective removal of weeds in managing croplands and lawns. Worldwide use of defoliants, ...

and eventual death. It has been determined that this infection is caused by the fungus ''

Blumeriella kerriae ''Blumeriella kerriae'' is a species of fungus in the family Drepanopezizaceae. Taxonomy ''Blumeriella kerriae'' was described by Vern Bonham Stewart in 1917 as ''Cylindrosporium kerriae'', with the basionym ''Coccomyces kerriae''. The specie ...

'', which is specific to the kerria. This highly contagious disease, known in English as kerria twig and leaf blight, was known in the U.S. but has not previously been observed on British plants. It is regarded as a serious threat to the cultivated kerria plants, which are popular garden shrubs.

Medicinal use

The plant has

anti-inflammatory Anti-inflammatory is the property of a substance or treatment that reduces inflammation, fever or swelling. Anti-inflammatory drugs, also called anti-inflammatories, make up about half of analgesics. These drugs reduce pain by inhibiting mechan ...

properties and a

decoction Decoction is a method of extraction by boiling herbal or plant material (which may include stems, roots, bark and rhizomes) to dissolve the chemicals of the material. It is the most common preparation method in various herbal medicine systems. D ...

of the flowering shoots with

honey Honey is a sweet and viscous substance made by several species of bees, the best-known of which are honey bees. Honey is made and stored to nourish bee colonies. Bees produce honey by gathering and then refining the sugary secretions of pl ...

has been used in China in the treatment of

cough A cough is a sudden expulsion of air through the large breathing passages which can help clear them of fluids, irritants, foreign particles and Microorganism, microbes. As a protective reflex, coughing can be repetitive with the cough reflex fol ...

s and gynecological disorders.

Chemistry

The leaves and roots contain 0.002%

hydrogen cyanide Hydrogen cyanide (formerly known as prussic acid) is a chemical compound with the chemical formula, formula HCN and structural formula . It is a highly toxic and flammable liquid that boiling, boils slightly above room temperature, at . HCN is ...

, while the tender shoots are a rich source of

vitamin C Vitamin C (also known as ascorbic acid and ascorbate) is a water-soluble vitamin found in citrus and other fruits, berries and vegetables. It is also a generic prescription medication and in some countries is sold as a non-prescription di ...

(200 mg per 100 g) and the seeds contain 44.9%

protein Proteins are large biomolecules and macromolecules that comprise one or more long chains of amino acid residue (biochemistry), residues. Proteins perform a vast array of functions within organisms, including Enzyme catalysis, catalysing metab ...

and 45.3%

fat In nutrition science, nutrition, biology, and chemistry, fat usually means any ester of fatty acids, or a mixture of such chemical compound, compounds, most commonly those that occur in living beings or in food. The term often refers specif ...

. The flower petals contain the ''O''-methylated flavonoid

pectolinarin Pectolinarin is a ''Cirsium ''Cirsium'' is a genus of Perennial plant, perennial and Biennial plant, biennial flowering plants in the Asteraceae, one of several genera known commonly as thistles. They are more precisely known as plume thistles. ...

, (5,7-dihydroxy-4,6-dimethoxyflavone-7-rutinoside), a

cytotoxic Cytotoxicity is the quality of being toxic to cells. Examples of toxic agents are toxic metals, toxic chemicals, microbe neurotoxins, radiation particles and even specific neurotransmitters when the system is out of balance. Also some types of dr ...

compound known also as Neolinarin and found also in ''

Linaria ''Linaria'' is a genus of almost 200 species of flowering plants, one of several related groups commonly called toadflax. They are annuals and herbaceous perennials, and the largest genus in the Antirrhineae tribe of the plantain family Plant ...

'' species, ''

Kickxia elatine ''Kickxia elatine'' (commonly known as sharpleaf cancerwort and sharp-leaved fluellen) is a species of flowering plant in the family Plantaginaceae. It is native to Europe and Asia, but it is present on other continents as an introduced species, ...

'' and the '' Duranta'' species ''D. plumieri''.

In culture

''Kerria japonica'' is mentioned frequently in the ''

Man'yōshū The is the oldest extant collection of Japanese (poetry in Classical Japanese), compiled sometime after AD 759 during the Nara period. The anthology is one of the most revered of Japan's poetic compilations. The compiler, or the last in ...

'', the oldest extant collection of Japanese poetry from the AD first millennium. In addition, the Japanese call the golden yellow color (variously #FFA400, #FFBF00, #F8B500) between orange and yellow ''yamabuki'' color ( ''yamabuki-iro''), from the name of the plant.

Qing Dynasty The Qing dynasty ( ), officially the Great Qing, was a Manchu-led Dynasties of China, imperial dynasty of China and an early modern empire in East Asia. The last imperial dynasty in Chinese history, the Qing dynasty was preceded by the ...

poet Chen Hao () celebrated the beauty of ''Kerria japonica'' in his agricultural treatise the ().

References

External links

* * {{Authority control Kerrieae Flora of Japan Flora of China Flora of Korea Plants described in 1771