''Rhododendron luteum'', the yellow azalea or honeysuckle azalea, 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 appropriate s ...

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 th ...

in the heath

family Family (from la, familia) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its ...

Ericaceae,

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 southeastern Europe and southwest Asia. In Europe, it occurs from southern Poland and Austria south through the

Balkans The Balkans ( ), also known as the Balkan Peninsula, is a geographical area in southeastern Europe with various geographical and historical definitions. The region takes its name from the Balkan Mountains that stretch throughout the who ...

and east to southern Russia; and in Asia, east to the

Caucasus The Caucasus () or Caucasia (), is a region between the Black Sea and the Caspian Sea, mainly comprising Armenia, Azerbaijan, Georgia, and parts of Southern Russia. The Caucasus Mountains, including the Greater Caucasus range, have historically ...

. It is a

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 ...

growing . The leaves are

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, aft ...

, 5–10 cm long and 2–4 cm broad. The flowers are 3–4 cm in diameter, bright yellow, and strongly perfumed, produced in trusses of 5-25 together. The fruit is a dry capsule 15–25 mm long, containing numerous small seeds. Despite the sweet perfume of the flowers, the

nectar Nectar is a sugar-rich liquid produced by plants in glands called nectaries or nectarines, either within the flowers with which it attracts pollinating animals, or by extrafloral nectaries, which provide a nutrient source to animal mutualists ...

toxic Toxicity is the degree to which a chemical substance or a particular mixture of substances can damage an organism. Toxicity can refer to the effect on a whole organism, such as an animal, bacterium, or plant, as well as the effect on a subst ...

, containing

grayanotoxin Grayanotoxins are a group of closely related neurotoxins named after '' Leucothoe grayana'', a plant native to Japan originally named for 19th century American botanist Asa Gray. Grayanotoxin I (grayanotaxane-3,5,6,10,14,16-hexol 14-acetate) is als ...

; records of

poisoning A poison can be any substance that is harmful to the body. It can be swallowed, inhaled, injected or absorbed through the skin. Poisoning is the harmful effect that occurs when too much of that substance has been taken. Poisoning is not to ...

of people eating the honey date back to the 4th century BC in

Classical Greece Classical Greece was a period of around 200 years (the 5th and 4th centuries BC) in Ancient Greece,The "Classical Age" is "the modern designation of the period from about 500 B.C. to the death of Alexander the Great in 323 B.C." ( Thomas R. Marti ...

Cultivation and uses

It is widely cultivated in western Europe, used both 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 i ...

in its own right, and as a

rootstock A rootstock is part of a plant, often an underground part, from which new above-ground growth can be produced. It could also be described as a stem with a well developed root system, to which a bud from another plant is grafted. It can refer to a ...

onto which other

azalea Azaleas are flowering shrubs in the genus ''Rhododendron'', particularly the former sections ''Tsutsusi'' (evergreen) and '' Pentanthera'' (deciduous). Azaleas bloom in the spring (April and May in the temperate Northern Hemisphere, and Octob ...

cultivar 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, ...

s are

grafted Grafting or graftage is a horticultural technique whereby tissues of plants are joined so as to continue their growth together. The upper part of the combined plant is called the scion () while the lower part is called the rootstock. The succ ...

. It is locally

naturalised Naturalization (or naturalisation) is the legal act or process by which a non-citizen of a country may acquire citizenship or nationality of that country. It may be done automatically by a statute, i.e., without any effort on the part of the i ...

in western and northern Europe. In Great Britain it has colonised many wet

heaths A heath () is a shrubland habitat found mainly on free-draining infertile, acidic soils and characterised by open, low-growing woody vegetation. Moorland is generally related to high-ground heaths with—especially in Great Britain—a cooler a ...

and

bog A bog or bogland is a wetland that accumulates peat as a deposit of dead plant materials often mosses, typically sphagnum moss. It is one of the four main types of wetlands. Other names for bogs include mire, mosses, quagmire, and muskeg; a ...

s, but unlike its relative ''

Rhododendron ponticum ''Rhododendron ponticum'', called common rhododendron or pontic rhododendron, is a species of ''Rhododendron'' native to the Iberian Peninsula in southwest Europe and the Caucasus region in northern West Asia. Description ''R. ponticum'' is a d ...

'' it does not usually form dominant stands and so is of lower nature conservation concern. However it is listed under Schedule 9 of the UK

Wildlife and Countryside Act 1981 The Wildlife and Countryside Act 1981 is an Act of Parliament in the United Kingdom implemented to comply with European Council Directive 79/409/EEC on the conservation of wild birds. In short, the act gives protection to native species (especia ...

as a non-native invasive species. While it is legal to sell and grow it in gardens, users are expected to take care when disposing of material from this plant. ''R. luteum'' has 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 (Nort ...

’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 ...

Cultural references

The plant is depicted instead of the crown above the coat of arms of the Local Community of Boštanj. It has been chosen because the area is one of the rare growing places of ''Rhododendron luteum'' in

Slovenia Slovenia ( ; sl, Slovenija ), officially the Republic of Slovenia (Slovene: , abbr.: ''RS''), is a country in Central Europe. It is bordered by Italy to the west, Austria to the north, Hungary to the northeast, Croatia to the southeast, an ...

. The coat of arms was created in 1998 by the artist Rudi Stopar.

Gallery

Sarı çiçekli ormangülü-1.jpg Rhododendron luteum i Oslo.jpg, Fruit Rhododendron luteum BotGardBln1105Autumn.JPG, Autumn foliage Hachmann Rhod Goldtopas.jpg, Cultivar ‘Goldtopas’

References

Flora Europaea: ''Rhododendron luteum''
*
Plants for a Future: ''Rhododendron luteum''
{{Taxonbar, from=Q2591210 luteum Flora of Armenia Flora of Austria Flora of Azerbaijan Flora of Belarus Flora of Georgia (country) Flora of Greece Flora of Italy Flora of Moldova Flora of Poland Flora of Russia Flora of Slovenia Flora of Turkey Flora of Ukraine Poisonous plants