mountain laurel

Mountain-Laurel
Kalmia latifolia flowers
Scientific classification
Kingdom:	Plantae
(unranked):	Angiosperms
(unranked):	Eudicots
(unranked):	Asterids
Order:	Ericales
Family:	Ericaceae
Genus:	Kalmia
Species:	K. latifolia
Binomial name
Kalmia latifolia L.

Wikimedia Commons has media related to: Kalmia latifolia

Kalmia latifolia, commonly called Mountain-laurel or Spoonwood, is a flowering plant in the family Ericaceae, native to the eastern United States, from southern Maine south to northern Florida, and west to Indiana and Louisiana. Mountain-laurel is the state flower of Connecticut and Pennsylvania. It is the namesake of the city of Laurel, Mississippi (founded 1882).

Growth

It is an evergreen shrub growing to 3–9 m tall. The leaves are 3–12 cm long and 1–4 cm wide. Its flowers are round, ranging from light pink to white, and occurring in clusters. There are several named cultivars today that have darker shades of pink, near red and maroon pigment. It blooms between May and June. All parts of the plant are poisonous. Roots are fibrous, matted.^[1]

The plant is naturally found on rocky slopes and mountainous forest areas. It prefers a soil pH in the 4.5 to 5.5 range, therefore it thrives in acid soil. The plant often grows in large thickets, covering large areas of forest floor. In North America it can become tree sized on undeveloped mountains of the Carolinas but is a shrub further north.^[1]

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, who sent samples to Linnaeus in the 18th century.

Cultivation and uses

The plant was originally brought to Europe as an ornamental plant during the 18th century. It is still widely grown for its attractive flowers. Numerous cultivars have been selected with varying flower color. Many of the cultivars have originated from the Connecticut Experiment Station, Hamden, CT, and from the plant breeding of Dr Richard Jaynes. Jaynes has numerous named varieties that he has created and he is considered the world's authority on Kalmia latifolia.^{[citation needed]}

A little known American use of the plant was in the making of arbors for early wooden-works clocks. Mountain-laurel is a foodplant of last resort for gypsy moth caterpillars, utilized only during outbreaks when moth densities are extremely high.

Toxicity

Mountain laurel is poisonous to several different animals, including horses, goats, cattle, sheep, and deer, due to andromedotoxin and arbutin. The green parts of the plant, the flowers, twigs, and pollen are all toxic, and symptoms of toxicity begin to appear about 6 hours following ingestion. Poisoning produces anorexia, repeated swallowing, profuse salivation, depression, uncoordination, vomiting, frequent defecation, watering of the eyes, irregular or difficulty breathing, weakness, cardiac distress, convulsions, coma, and eventually death. Autopsy will show gastrointestinal irritation and hemorrhage.

Gallery

K. latifolia flower buds.	More mature buds of wild K. latifolia, showing the geometry.	Leaves and early buds	a Kalmia latifolia cultivar
			Flowers, both blooming and wilted, on the same flower head.‎

See also

• List of late spring flowers
• List of early summer flowers
• List of plants poisonous to equines

References

• Germplasm Resources Information Network: Kalmia latifolia
• USDA Plant Profile: Kalmia latifolia
• Connecticut Botanical Society Profile: Kalmia latifolia
• Kalmia latifolia images at bioimages.vanderbilt.edu