''Kalmia'' is a

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of living and fossil organisms as well as viruses. In the hierarchy of biological classification, genus comes above species and below family. In binomial nom ...

of about ten

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 ...

evergreen In botany, an evergreen is a plant which has foliage that remains green and functional through more than one growing season. This also pertains to plants that retain their foliage only in warm climates, and contrasts with deciduous plants, whic ...

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 tree ...

s from 0.2–5 m tall, in the family Ericaceae. They are native to

North America North America is a continent in the Northern Hemisphere and almost entirely within the Western Hemisphere. It is bordered to the north by the Arctic Ocean, to the east by the Atlantic Ocean, to the southeast by South America and th ...

(mainly in the eastern half of the continent) and

Cuba Cuba ( , ), officially the Republic of Cuba ( es, República de Cuba, links=no ), is an island country comprising the island of Cuba, as well as Isla de la Juventud and several minor archipelagos. Cuba is located where the northern Caribb ...

. They grow in

acid In computer science, ACID ( atomicity, consistency, isolation, durability) is a set of properties of database transactions intended to guarantee data validity despite errors, power failures, and other mishaps. In the context of databases, a se ...

ic soils, with different species in wet acid bog habitats (''K. angustifolia, K. polifolia'') and dry, sandy soils (''K. ericoides, K. latifolia''). ''Kalmia'' was named by Linnaeus to honour his friend the botanist

Pehr Kalm Pehr Kalm (6 March 1716 – 16 November 1779), also known as Peter Kalm, was a Swedish explorer, botanist, naturalist, and agricultural economist. He was one of the most important apostles of Carl Linnaeus. In 1747, he was commissioned by th ...

, who collected it in eastern North America during the mid-18th century. Earlier, Mark Catesby saw it during his travels in Carolina, and after his return to England in 1726, imported seeds. He described it, a costly rarity, in his ''Natural History of Carolina'', as ''Chamaedaphne foliis tini'', that is to say "with leaves like the

Laurustinus ''Viburnum tinus'', the laurustinus, laurustine or laurestine, is a species of flowering plant in the family Adoxaceae, native to the Mediterranean area of Europe and North Africa. ''Laurus'' signifies the leaves' similarities to bay laurel. Des ...

"; the botanist and plant-collector Peter Collinson, who had begged some of the shrub from his correspondent John Custis in Virginia, wrote, when his plants flowered, that "I Really Think it exceeds the Laurus Tinus." Mountain laurel blooms (5940253290)

The leaves are 2–12 cm long and simple lanceolate. 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 white, pink or purple, in corymbs of 10-50, reminiscent of Rhododendron flowers but flatter, with a star-like calyx of five conjoined petals; each flower is 1–3 cm diameter. 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 partic ...

is a five-lobed capsule, which splits to release the numerous small

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 ...

s. The foliage contains grayanotoxins, a group of closely related

neurotoxin Neurotoxins are toxins that are destructive to nerve tissue (causing neurotoxicity). Neurotoxins are an extensive class of exogenous chemical neurological insultsSpencer 2000 that can adversely affect function in both developing and mature nerv ...

s named after ''Leucothoe grayana'', native to Japan, so it is toxic if eaten, with

sheep Sheep or domestic sheep (''Ovis aries'') are domesticated, ruminant mammals typically kept as livestock. Although the term ''sheep'' can apply to other species in the genus '' Ovis'', in everyday usage it almost always refers to domesticate ...

being particularly prone to poisoning, hence the name lambkill used for some of the species. Other names for Kalmia, particularly ''Kalmia angustifolia,'' are sheep-laurel, lamb-kill, calf-kill, kill-kid, and sheep-poison,Natural History Education, Science, Technology
regarding alternate names, accessed March 30, 2007. which may be written with or without the hyphen. (See species list below.) "Kid" here refers to a young

goat The goat or domestic goat (''Capra hircus'') is a domesticated species of goat-antelope typically kept as livestock. It was domesticated from the wild goat (''C. aegagrus'') of Southwest Asia and Eastern Europe. The goat is a member of the a ...

, not a human child, but the foliage and twigs are toxic to humans as well. It has also been called

spoonwood Spoonwood is a common name for two plants: *''Kalmia latifolia ''Kalmia latifolia'', the mountain laurel, calico-bush, or spoonwood, is a species of flowering plant in the heath family Ericaceae, that is native to the eastern United States. Its ...

because Kalm was told by Dutch settlers of North America that Native Americans made spoons from the wood. Given its toxicity, this may be folklore rather than scientific fact. Kalmias are popular

garden A garden is a planned space, usually outdoors, set aside for the cultivation, display, and enjoyment of plants and other forms of nature. The single feature identifying even the wildest wild garden is ''control''. The garden can incorporate bot ...

shrubs, grown for their decorative flowers. They should not be planted where they are accessible to livestock due to the toxicity. ''Kalmia'' species are used as food plants by the

larva A larva (; plural larvae ) is a distinct juvenile form many animals undergo before metamorphosis into adults. Animals with indirect development such as insects, amphibians, or cnidarians typically have a larval phase of their life cycle. ...

e of some

lepidoptera Lepidoptera ( ) is an order of insects that includes butterflies and moths (both are called lepidopterans). About 180,000 species of the Lepidoptera are described, in 126 families and 46 superfamilies, 10 percent of the total described speci ...

n species including '' Coleophora kalmiella'' which feeds exclusively on ''Kalmia''.

Species

Species (and

infraspecific taxa In botany, an infraspecific name is the scientific name for any taxon below the rank of species, i.e. an infraspecific taxon or infraspecies. (A "taxon", plural "taxa", is a group of organisms to be given a particular name.) The scientific names ...

) listed by The Plant List as "Accepted": * '' Kalmia angustifolia'' L. - Sheep-laurel, lambkill * '' Kalmia buxifolia'' (Bergius) Gift & Kron - Sandmyrtle * '' Kalmia carolina'' Small - Carolina mountain-laurel * '' Kalmia cuneata'' Michx. - Whitewicky * '' Kalmia ericoides'' C.Wright ex Griseb. - Cuban kalmia ** ''Kalmia ericoides'' var. ''aggregata'' (Small) Ebinger * '' Kalmia hirsuta'' Walter - Hairy mountain-laurel * '' Kalmia latifolia'' L. - Lambkill ** ''Kalmia latifolia'' f. ''alba'' (Mouill.) Rehder ** ''Kalmia latifolia'' f. ''fuscata'' (Rehder) Rehder ** ''Kalmia latifolia'' f. ''obtusata'' (Rehder) Rehder ** ''Kalmia latifolia'' f. ''polypetala'' (G.Nicholson) Rehder * ''

Kalmia microphylla ''Kalmia microphylla'', known as alpine laurel, bog laurel, swamp-laurel, western bog-laurel or western laurel, is a species of ''Kalmia'' of the family Ericaceae. It is native to North America and can be found throughout the western US and weste ...

'' (Hook.) A.Heller - Alpine laurel, alpine bog-laurel, alpine mountain-laurel ** ''Kalmia microphylla'' subsp. ''occidentalis'' (Small) Roy L.Taylor & MacBryde * ''

Kalmia polifolia ''Kalmia polifolia'', previously known as ''Kalmia glauca'' and commonly called bog laurel, swamp laurel, or pale laurel, is a perennial evergreen shrub of cold acidic bogs, in the family Ericaceae. It is native to north-eastern North America, f ...

'' Wangenh. - Bog kalmia, bog-laurel * '' Kalmia simulata'' (Britton & M.Wilson) Southall '' Kalmia procumbens'' is a widely accepted member of this genus, though it is the only species in the genus ''Loiseleuria'' according to The Plant List. The related ''

Kalmiopsis ''Kalmiopsis'' is a small genus of flowering plants in the family Ericaceae. Species It contains two species, which are endemic to Oregon in the United States.Kalmiopsis leachiana ''Kalmiopsis leachiana'', commonly referred to as kalmiopsis, is a rare flowering plant endemic to the Siskiyou Mountains of southwest Oregon, where it is specially protected in the Kalmiopsis Wilderness reserve. It was discovered in 1930 by L ...

'' and '' K. fragrans'') is a rare shrub

endemic Endemism is the state of a species being found in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also found else ...

to southwest

Oregon Oregon () is a U.S. state, state in the Pacific Northwest region of the Western United States. The Columbia River delineates much of Oregon's northern boundary with Washington (state), Washington, while the Snake River delineates much of it ...

. File:FFH-Gebiet "Altwarmbüchener Moor" (cropped).JPG, ''Kalmia angustifolia'' File:Kalmia buxifolia NRCS-2.jpg, ''Kalmia buxifolia'' File:Mountain Laurel - Flickr - treegrow (13).jpg, ''Kalmia latifolia'' File:Western Bog Laurel (cropped).jpg, ''Kalmia microphylla'' File:Kalmia polifolia.jpg, ''Kalmia polifolia''

Fossil record

Fossil A fossil (from Classical Latin , ) is any preserved remains, impression, or trace of any once-living thing from a past geological age. Examples include bones, shells, exoskeletons, stone imprints of animals or microbes, objects preserved ...

leaves of †''Kalmia saxonica'' have been described from the Lower Miocene of

Brandis Brandis () is a town in the Leipzig district, in Saxony, Germany. It is situated 16 km east of Leipzig Leipzig ( , ; Upper Saxon: ) is the most populous city in the German state of Saxony. Leipzig's population of 605,407 inhabitant ...

Germany Germany,, officially the Federal Republic of Germany, is a country in Central Europe. It is the second most populous country in Europe after Russia, and the most populous member state of the European Union. Germany is situated betwee ...

and Bełchatów,

Poland Poland, officially the Republic of Poland, is a country in Central Europe. It is divided into 16 administrative provinces called voivodeships, covering an area of . Poland has a population of over 38 million and is the fifth-most populou ...

, †Kalmia marcodurensis'' have been described from the Lower Miocene of Bitterfeld,

. In the Late Tertiary ''Kalmia'' was associated with coal-forming vegetation occurring as a component of the vegetation of bush swamps together with '' Cyrilla'' and other shrubs. Among recent species '' Kalmia angustifolia'' is most similar to †''Kalmia saxonica'' in respect of morphology, while '' Kalmia latifolia'' has a very similar epidermal structure. These two extant species grow in the eastern part of

from (

Quebec Quebec ( ; )According to the Canadian government, ''Québec'' (with the acute accent) is the official name in Canadian French and ''Quebec'' (without the accent) is the province's official name in Canadian English is one of the thirte ...

Florida Florida is a state located in the Southeastern region of the United States. Florida is bordered to the west by the Gulf of Mexico, to the northwest by Alabama, to the north by Georgia, to the east by the Bahamas and Atlantic Ocean, and ...

) on acid swampy or marshy soils. Acta Palaeobotanica - Supplementum No. 3 - New Fossil Floras from Neogene Deposits in the Bełchatów Lignite Mine by Grzegor Worobiec - Polish Academy of Sciences, W. Szafer Institute of Botany, Krakow 2003

Bibliography

Books

* Jaynes, Richard A., 1997: Kalmia, mountain laurel and related species, Timber Press, Portland, Oregon, U.S.A. * Huebbers, Karl-Heinz and Westhoff, Julia,2020 : Fascynujące kalmie (Fascinating Kalmie) published by Plantin, Krakow, Poland ISBN: 978-83-956964-0-4

References

External links

European Kalmia SocietyKalmia.info: German Kalmia hybridizersPieris.eu: Info about ''Kalmia latifolia''
{{Taxonbar, from=Q1427635 Ericaceae genera Taxa named by Carl Linnaeus