''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 leaves, usually in the autumn; to the shedding of petals, afte ...
, yellow-flowering
shrub
A shrub (often also called a 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 ...
in the rose
family
Family (from la, familia) is a group of people related either by consanguinity (by recognized birth) or affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its members and of society. Ideall ...
(
Rosaceae
Rosaceae (), the rose family, is a medium-sized family of flowering plants that includes 4,828 known species in 91 genera.
The name is derived from the type genus ''Rosa''. Among the most species-rich genera are '' Alchemilla'' (270), ''Sorbus ...
),
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 entertai ...
to China, Japan and Korea. 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, ''K. japonica'' 'Pleniflora', is commonly called bachelor's buttons.
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 cultivar 'Pleniflora'.
It is sometimes known by the Japanese ''yamabuki'' (, Chinese pronunciation of characters ''shānchuī'') (= "mountain
butterbur
''Petasites'' is a genus of flowering plants in the sunflower family, Asteraceae, that are commonly referred to as butterburs and coltsfoots.
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, ste ...
are alternate, simple, 3–10 cm long, with a doubly serrated margin. 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 golden yellow, with five
petals
Petals are modified leaves that surround the reproductive parts of flowers. They are often brightly colored or unusually shaped to attract pollinators. All of the petals of a flower are collectively known as the ''corolla''. Petals are usually ...
, and evenly-spaced along branches of new green growth. The
fruit
In botany, a fruit is the seed-bearing structure in flowering plants that is formed from the ovary after flowering.
Fruits are the means by which flowering plants (also known as angiosperms) disseminate their seeds. Edible fruits in particul ...
is a dry single-
seed
A seed is an Plant embryogenesis, embryonic plant enclosed in a testa (botany), 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, includ ...
ed
achene
An achene (; ), also sometimes called akene and occasionally achenium or achenocarp, is a type of simple dry fruit produced by many species of flowering plants. Achenes are monocarpellate (formed from one carpel) and indehiscent (they do not ope ...
4–4.5 mm 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 type of cultivated plant that people have selected for desired traits and when propagated retain those traits. Methods used to propagate cultivars include: division, root and stem cuttings, offsets, grafting, tissue culture, ...
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 (N ...
's
Award of Garden Merit
The Award of Garden Merit (AGM) is a long-established annual award for plants by the British Royal Horticultural Society (RHS). It is based on assessment of the plants' performance under UK growing conditions.
History
The Award of Garden Merit ...
, ''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 lesions on the stems, resulting in
defoliation
A defoliant is any herbicidal chemical sprayed or dusted on plants to cause their leaves to fall off. Defoliants are widely used for the selective removal of weeds in managing croplands and lawns. Worldwide use of defoliants, along with the ...
and eventual death. It has been determined that this infection is caused by the fungus '' Blumeriella kerriae'', 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 or swelling. Anti-inflammatory drugs, also called anti-inflammatories, make up about half of analgesics. These drugs remedy pain by reducing inflammation as op ...
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. De ...
of the flowering shoots with
honey
Honey is a sweet and viscous substance made by several 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 plants (primaril ...
has been used in China in the treatment of
cough
A cough is a sudden expulsion of air through the large breathing passages that can help clear them of fluids, irritants, foreign particles and microbes. As a protective reflex, coughing can be repetitive with the cough reflex following three phas ...
s and gynecological disorders.Duke, A. and Ayensu, Edward S., ''Medicinal Plants of China'', pub. Reference Publications, inc. 1985 vol. II p.546.
Chemistry
The leaves and roots contain 0.002%
Hydrogen cyanide
Hydrogen cyanide, sometimes called prussic acid, is a chemical compound with the formula HCN and structure . It is a colorless, extremely poisonous, and flammable liquid that boils slightly above room temperature, at . HCN is produced on an in ...
, 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 and vegetables, also sold as a dietary supplement and as a topical 'serum' ingredient to treat melasma (dark pigment spots) and ...
(200 mg/100g) and the seeds contain 44.9% protein and 45.3%
fat
In nutrition, biology, and chemistry, fat usually means any ester of fatty acids, or a mixture of such compounds, most commonly those that occur in living beings or in food.
The term often refers specifically to triglycerides (triple est ...
. The flower petals contain the
O-methylated flavonoid The O-methylated flavonoids or methoxyflavonoids are flavonoids with methylations on hydroxyl groups (methoxy bonds). O-methylation has an effect on the solubility of flavonoids.
Enzymes
O-methylated flavonoids formation implies the presence of spe ...
pectolinarin, (5,7-dihydroxy-4,6-dimethoxyflavone-7-rutinoside), a
cytotoxic
Cytotoxicity is the quality of being toxic to cells. Examples of toxic agents are an immune cell or some types of venom, e.g. from the puff adder (''Bitis arietans'') or brown recluse spider (''Loxosceles reclusa'').
Cell physiology
Treating cel ...
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 Plantag ...
spp.,
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
''Duranta'' is a genus of flowering plants in the verbena family, Verbenaceae. It contains 17 species of shrubs and small trees that are native from southern Florida to Mexico and South America. They are commonly cultivated as hedges and ornamen ...
species ''D. plumieri''.Blunt, John W. and Munro, Murray H. G. ''Dictionary of Marine Natural Products'' pub. Chapman & Hall/CRC Taylor and Francis Group 2007 page 614.
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 imperial dynasty of China and the last orthodox dynasty in Chinese history. It emerged from the Later Jin dynasty founded by the Jianzhou Jurchens, a Tungusic-speaki ...
poet Chen Hao () celebrated the beauty of ''Kerria japonica'' in his agricultural treatise the ().