Kalmia latifolia
Encyclopedia
Kalmia latifolia, commonly called Mountain-laurel or Spoonwood, is a species of flowering plant
Flowering plant
The flowering plants , also known as Angiospermae or Magnoliophyta, are the most diverse group of land plants. Angiosperms are seed-producing plants like the gymnosperms and can be distinguished from the gymnosperms by a series of synapomorphies...
in the blueberry
Blueberry
Blueberries are flowering plants of the genus Vaccinium with dark-blue berries and are perennial...
family, Ericaceae
Ericaceae
The Ericaceae, commonly known as the heath or heather family, is a group of mostly calcifuge flowering plants. The family is large, with roughly 4000 species spread across 126 genera, making it the 14th most speciose family of flowering plants...
, that is native to the eastern United States
Eastern United States
The Eastern United States, the American East, or simply the East is traditionally defined as the states east of the Mississippi River. The first two tiers of states west of the Mississippi have traditionally been considered part of the West, but can be included in the East today; usually in...
. Its range stretches from southern Maine
Maine
Maine is a state in the New England region of the northeastern United States, bordered by the Atlantic Ocean to the east and south, New Hampshire to the west, and the Canadian provinces of Quebec to the northwest and New Brunswick to the northeast. Maine is both the northernmost and easternmost...
south to northern Florida
Florida
Florida is a state in the southeastern United States, located on the nation's Atlantic and Gulf coasts. It is bordered to the west by the Gulf of Mexico, to the north by Alabama and Georgia and to the east by the Atlantic Ocean. With a population of 18,801,310 as measured by the 2010 census, it...
, and west to Indiana
Indiana
Indiana is a US state, admitted to the United States as the 19th on December 11, 1816. It is located in the Midwestern United States and Great Lakes Region. With 6,483,802 residents, the state is ranked 15th in population and 16th in population density. Indiana is ranked 38th in land area and is...
and Louisiana
Louisiana
Louisiana is a state located in the southern region of the United States of America. Its capital is Baton Rouge and largest city is New Orleans. Louisiana is the only state in the U.S. with political subdivisions termed parishes, which are local governments equivalent to counties...
. Mountain-laurel is the state flower of Connecticut
Connecticut
Connecticut is a state in the New England region of the northeastern United States. It is bordered by Rhode Island to the east, Massachusetts to the north, and the state of New York to the west and the south .Connecticut is named for the Connecticut River, the major U.S. river that approximately...
and Pennsylvania
Pennsylvania
The Commonwealth of Pennsylvania is a U.S. state that is located in the Northeastern and Mid-Atlantic regions of the United States. The state borders Delaware and Maryland to the south, West Virginia to the southwest, Ohio to the west, New York and Ontario, Canada, to the north, and New Jersey to...
. It is the namesake of the city of Laurel, Mississippi
Laurel, Mississippi
Laurel is a city located in Jones County in Mississippi, a state of the United States of America. As of the 2000 census, the city had a total population of 18,393 although a significant population increase has been reported following Hurricane Katrina. Located in southeast Mississippi, southeast of...
(founded 1882).
Growth
It is an evergreenEvergreen
In botany, an evergreen plant is a plant that has leaves in all seasons. This contrasts with deciduous plants, which completely lose their foliage during the winter or dry season.There are many different kinds of evergreen plants, both trees and shrubs...
shrub
Shrub
A shrub or bush is distinguished from a tree by its multiple stems and shorter height, usually under 5–6 m tall. A large number of plants may become either shrubs or trees, depending on the growing conditions they experience...
growing to 3–9 m tall. The leaves
Leaf
A leaf is an organ of a vascular plant, as defined in botanical terms, and in particular in plant morphology. Foliage is a mass noun that refers to leaves as a feature of plants....
are 3–12 cm long and 1–4 cm wide. Its flower
Flower
A flower, sometimes known as a bloom or blossom, is the reproductive structure found in flowering plants . The biological function of a flower is to effect reproduction, usually by providing a mechanism for the union of sperm with eggs...
s are round, ranging from light pink to white, and occurring in clusters. There are several named cultivar
Cultivar
A cultivar'Cultivar has two meanings as explained under Formal definition. When used in reference to a taxon, the word does not apply to an individual plant but to all those plants sharing the unique characteristics that define the cultivar. is a plant or group of plants selected for desirable...
s today that have darker shades of pink, near red and maroon pigment. It blooms in May and June. All parts of the plant are poison
Poison
In the context of biology, poisons are substances that can cause disturbances to organisms, usually by chemical reaction or other activity on the molecular scale, when a sufficient quantity is absorbed by an organism....
ous. Root
Root
In vascular plants, the root is the organ of a plant that typically lies below the surface of the soil. This is not always the case, however, since a root can also be aerial or aerating . Furthermore, a stem normally occurring below ground is not exceptional either...
s are fibrous
Fiber
Fiber is a class of materials that are continuous filaments or are in discrete elongated pieces, similar to lengths of thread.They are very important in the biology of both plants and animals, for holding tissues together....
and matted.
The plant is naturally found on rocky slopes and mountain
Mountain
Image:Himalaya_annotated.jpg|thumb|right|The Himalayan mountain range with Mount Everestrect 58 14 160 49 Chomo Lonzorect 200 28 335 52 Makalurect 378 24 566 45 Mount Everestrect 188 581 920 656 Tibetan Plateaurect 250 406 340 427 Rong River...
ous forest
Forest
A forest, also referred to as a wood or the woods, is an area with a high density of trees. As with cities, depending where you are in the world, what is considered a forest may vary significantly in size and have various classification according to how and what of the forest is composed...
areas. It thrives in acid
Acid
An acid is a substance which reacts with a base. Commonly, acids can be identified as tasting sour, reacting with metals such as calcium, and bases like sodium carbonate. Aqueous acids have a pH of less than 7, where an acid of lower pH is typically stronger, and turn blue litmus paper red...
ic soil, preferring a soil pH
Soil pH
The soil pH is a measure of the acidity or basicity in soils. pH is defined as the negative logarithm of the activity of hydrogen ions in solution. It ranges from 0 to 14, with 7 being neutral. A pH below 7 is acidic and above 7 is basic. Soil pH is considered a master variable in soils as it...
in the 4.5 to 5.5 range. The plant often grows in large thicket
Thicket
A thicket is a very dense stand of trees or tall shrubs, often dominated by only one or a few species, to the exclusion of all others. They may be formed by species that shed large amounts of highly viable seeds that are able to germinate in the shelter of the maternal plants.In some conditions the...
s, covering great areas of forest floor
Forest floor
The forest floor, also called detritus, duff and the O horizon, is one of the most distinctive features of a forest ecosystem. It mainly consists of shed vegetative parts, such as leaves, branches, bark, and stems, existing in various stages of decomposition above the soil surface...
. In North America
North America
North America is a continent wholly within the Northern Hemisphere and almost wholly within the Western Hemisphere. It is also considered a northern subcontinent of the Americas...
it can become tree sized on undeveloped mountains of the Carolinas but is a shrub
Shrub
A shrub or bush is distinguished from a tree by its multiple stems and shorter height, usually under 5–6 m tall. A large number of plants may become either shrubs or trees, depending on the growing conditions they experience...
farther north. The species is a frequent component of oak-heath forests.
Etymology
It is also known as Ivybush, Calico Bush, Spoonwood (because native Americans used to make their spoons out of it), Sheep Laurel, Lambkill and Clamoun.The plant was first recorded in America in 1624, but it was named after Pehr Kalm
Pehr Kalm
Pehr Kalm was a Swedish-Finnish explorer, botanist, naturalist, and agricultural economist. He was one of most important apostles of Carl Linnaeus...
, who sent samples to Linnaeus in the 18th century.
Cultivation and uses
The plant was originally brought to EuropeEurope
Europe is, by convention, one of the world's seven continents. Comprising the westernmost peninsula of Eurasia, Europe is generally 'divided' from Asia to its east by the watershed divides of the Ural and Caucasus Mountains, the Ural River, the Caspian and Black Seas, and the waterways connecting...
as an ornamental plant
Ornamental plant
Ornamental plants are plants that are grown for decorative purposes in gardens and landscape design projects, as house plants, for cut flowers and specimen display...
during the 18th century. It is still widely grown for its attractive flower
Flower
A flower, sometimes known as a bloom or blossom, is the reproductive structure found in flowering plants . The biological function of a flower is to effect reproduction, usually by providing a mechanism for the union of sperm with eggs...
s. Numerous cultivar
Cultivar
A cultivar'Cultivar has two meanings as explained under Formal definition. When used in reference to a taxon, the word does not apply to an individual plant but to all those plants sharing the unique characteristics that define the cultivar. is a plant or group of plants selected for desirable...
s have been selected with varying flower color. Many of the cultivars have originated from the Connecticut Experiment Station in Hamden
Hamden, Connecticut
Hamden is a town in New Haven County, Connecticut, United States. The town's nickname is "The Land of the Sleeping Giant." Hamden is home to Quinnipiac University. The population was 58,180 according to the Census Bureau's 2005 estimates...
and from the plant breeding of Dr. Richard Jaynes. Jaynes has numerous named varieties that he has created and is considered the world's authority on Kalmia latifolia.
The wood of the mountain laurel is heavy and strong but brittle. It has never been a viable commercial crop as it does not grow large enough yet it is suitable for wreaths, furniture, bowls and other household items. It was used in the early 19th century in wooden-works clocks. Burl
Burl
A burl or bur or burr is a tree growth in which the grain has grown in a deformed manner. It is commonly found in the form of a rounded outgrowth on a tree trunk or branch that is filled with small knots from dormant buds.A burl results from a tree undergoing some form of stress. It may be caused...
s were used for pipe bowls in place of imported briar burls. It can be used for handrail
Handrail
A handrail is a rail that is designed to be grasped by the hand so as to provide stability or support. Handrails are commonly used while ascending or descending stairways and escalators in order to prevent injurious falls. Other applications include bathroom handrails—which help to prevent falls on...
s or guard rail
Guard rail
Guard rail or guardrail, sometimes referred to as guide rail or railing, is a system designed to keep people or vehicles from straying into dangerous or off-limits areas...
s. When used in a handrail, smaller diameter branches of less than 1.5 inches are preferred; branches larger in diameter than 1.5 inches can be used in exterior structures such as pergolas, gazebos, and bridge guardrails.
Mountain laurel is a food plant of last resort for gypsy moth
Gypsy moth
The gypsy moth, Lymantria dispar, is a moth in the family Lymantriidae of Eurasian origin. Originally ranging from Europe to Asia, it was introduced to North America in the late 1860s and has been expanding its range ever since...
caterpillar
Caterpillar
Caterpillars are the larval form of members of the order Lepidoptera . They are mostly herbivorous in food habit, although some species are insectivorous. Caterpillars are voracious feeders and many of them are considered to be pests in agriculture...
s, utilized only during outbreaks when moth densities are extremely high.
Toxicity
Mountain laurel is poisonPoison
In the context of biology, poisons are substances that can cause disturbances to organisms, usually by chemical reaction or other activity on the molecular scale, when a sufficient quantity is absorbed by an organism....
ous to several different animals due to andromedotoxin and arbutin
Arbutin
Arbutin is both an ether and a glycoside; a glycosylated hydroquinone extracted from bearberry plant in the genus Arctostaphylos. It inhibits tyrosinase and thus prevents the formation of melanin. Arbutin is therefore used as a skin-lightening agent. Arbutin is found in wheat, and is concentrated...
, including horse
Horse
The horse is one of two extant subspecies of Equus ferus, or the wild horse. It is a single-hooved mammal belonging to the taxonomic family Equidae. The horse has evolved over the past 45 to 55 million years from a small multi-toed creature into the large, single-toed animal of today...
s, goat
Goat
The domestic goat is a subspecies of goat domesticated from the wild goat of southwest Asia and Eastern Europe. The goat is a member of the Bovidae family and is closely related to the sheep as both are in the goat-antelope subfamily Caprinae. There are over three hundred distinct breeds of...
s, cattle
Cattle
Cattle are the most common type of large domesticated ungulates. They are a prominent modern member of the subfamily Bovinae, are the most widespread species of the genus Bos, and are most commonly classified collectively as Bos primigenius...
, sheep
Domestic sheep
Sheep are quadrupedal, ruminant mammals typically kept as livestock. Like all ruminants, sheep are members of the order Artiodactyla, the even-toed ungulates. Although the name "sheep" applies to many species in the genus Ovis, in everyday usage it almost always refers to Ovis aries...
, deer
Deer
Deer are the ruminant mammals forming the family Cervidae. Species in the Cervidae family include white-tailed deer, elk, moose, red deer, reindeer, fallow deer, roe deer and chital. Male deer of all species and female reindeer grow and shed new antlers each year...
, and monkeys and humans. It is not toxic to dog
Dog
The domestic dog is a domesticated form of the gray wolf, a member of the Canidae family of the order Carnivora. The term is used for both feral and pet varieties. The dog may have been the first animal to be domesticated, and has been the most widely kept working, hunting, and companion animal in...
s, cat
Cat
The cat , also known as the domestic cat or housecat to distinguish it from other felids and felines, is a small, usually furry, domesticated, carnivorous mammal that is valued by humans for its companionship and for its ability to hunt vermin and household pests...
s, or small household pets. The green parts of the plant, flower
Flower
A flower, sometimes known as a bloom or blossom, is the reproductive structure found in flowering plants . The biological function of a flower is to effect reproduction, usually by providing a mechanism for the union of sperm with eggs...
s, twigs, and pollen
Pollen
Pollen is a fine to coarse powder containing the microgametophytes of seed plants, which produce the male gametes . Pollen grains have a hard coat that protects the sperm cells during the process of their movement from the stamens to the pistil of flowering plants or from the male cone to the...
are all toxic, including food products made from them, such as honey. Symptoms of toxicity
Toxicity
Toxicity is the degree to which a substance can damage a living or non-living organisms. Toxicity can refer to the effect on a whole organism, such as an animal, bacterium, or plant, as well as the effect on a substructure of the organism, such as a cell or an organ , such as the liver...
begin to appear about 6 hours following ingestion. Symptoms include irregular or difficulty breathing, anorexia
Anorexia (symptom)
Anorexia is the decreased sensation of appetite...
, repeated swallowing, profuse salivation, watering of the eyes
Tears
Tears are secretions that clean and lubricate the eyes. Lacrimation or lachrymation is the production or shedding of tears....
and nose, cardiac distress, incoordination, depression, vomiting
Vomiting
Vomiting is the forceful expulsion of the contents of one's stomach through the mouth and sometimes the nose...
, frequent defecation
Defecation
Defecation is the final act of digestion by which organisms eliminate solid, semisolid or liquid waste material from the digestive tract via the anus. Waves of muscular contraction known as peristalsis in the walls of the colon move fecal matter through the digestive tract towards the rectum...
, weakness, convulsions, paralysis, coma
Coma
In medicine, a coma is a state of unconsciousness, lasting more than 6 hours in which a person cannot be awakened, fails to respond normally to painful stimuli, light or sound, lacks a normal sleep-wake cycle and does not initiate voluntary actions. A person in a state of coma is described as...
, and eventually death. Autopsy
Autopsy
An autopsy—also known as a post-mortem examination, necropsy , autopsia cadaverum, or obduction—is a highly specialized surgical procedure that consists of a thorough examination of a corpse to determine the cause and manner of death and to evaluate any disease or injury that may be present...
will show gastrointestinal irritation and hemorrhage
Bleeding
Bleeding, technically known as hemorrhaging or haemorrhaging is the loss of blood or blood escape from the circulatory system...
.