Dicerandra immaculata
Encyclopedia
Dicerandra immaculata is a rare species of flowering plant in the mint family
known by the common names Lakela's mint, Olga's mint, and spotless balm. It is endemic to Florida
in the United States, where it is known only from Indian River
and St. Lucie Counties
. There are seven occurrences of the plant, two of which are scheduled for destruction as the land is cleared for development. The plant was federally listed as an endangered species
in 1985.
This is an aromatic perennial shrub
growing up to about half a meter tall, with several erect stems emerging from a woody-topped taproot
. The narrow leaves are up to 3 centimeters long by 4 millimeters wide. The herbage is mint-scented. 1 to 3 flowers occur in the leaf axils. The flower is purplish pink in color and lacks the spots that those of many other Dicerandra have. The throat of the flower is tubular and not bent. The anthers of the flowers have tiny spurs that act as triggers, causing the flower to release pollen
when an insect arrives. There are now two varieties of this plant, with var. savannarum having been described in 2001. It has wider leaves and more limp branches than var. immaculata.
This plant grows in white- and yellow-sand Florida scrub
habitat
. It can be found in openings and slightly shady areas where the wind or wildfire
has cleared a partial or total space in the canopy. This habitat is becoming ever more rare today as it is consumed for development; Florida's population is growing rapidly. Several known populations of this plant have been destroyed in the process. Remaining tracts of land are very fragmented
.
There are not many predators that tolerate the strong oils of this mint, so herbivory is not a serious problem. Mildew
affects the flowers sometimes, however, causing fruit destruction. Invasive plant species
that threaten the habitat include Brazilian pepper (Schinus terebinthifolius), rosary pea (Abrus precatorius), Natal grass
(Rhynchelytrum repens), and Guinea grass
(Panicum maximum).
Some new populations of the species have been planted in areas that are protected, even though they are outside the known historical range of the plant.
Lamiaceae
The mints, taxonomically known as Lamiaceae or Labiatae, are a family of flowering plants. They have traditionally been considered closely related to Verbenaceae, but in the 1990s, phylogenetic studies suggested that many genera classified in Verbenaceae belong instead in Lamiaceae...
known by the common names Lakela's mint, Olga's mint, and spotless balm. It is endemic to 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...
in the United States, where it is known only from Indian River
Indian River County, Florida
Indian River County is a county located in the Treasure Coast region in the U.S. state of Florida. As of 2000, the population was 112,947. The U.S. Census Bureau 2005 estimate for the county is 128,594...
and St. Lucie Counties
St. Lucie County, Florida
St. Lucie County is a county located in the state of Florida. The county seat is the city of Fort Pierce. In the year 2000, the population was 192,695. As of the year 2010, the United States Census Bureau sets the population at 277,789.- History :...
. There are seven occurrences of the plant, two of which are scheduled for destruction as the land is cleared for development. The plant was federally listed as an endangered species
Endangered species
An endangered species is a population of organisms which is at risk of becoming extinct because it is either few in numbers, or threatened by changing environmental or predation parameters...
in 1985.
This is an aromatic perennial 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 up to about half a meter tall, with several erect stems emerging from a woody-topped taproot
Taproot
A taproot is an enlarged, somewhat straight to tapering plant root that grows vertically downward. It forms a center from which other roots sprout laterally.Plants with taproots are difficult to transplant...
. The narrow leaves are up to 3 centimeters long by 4 millimeters wide. The herbage is mint-scented. 1 to 3 flowers occur in the leaf axils. The flower is purplish pink in color and lacks the spots that those of many other Dicerandra have. The throat of the flower is tubular and not bent. The anthers of the flowers have tiny spurs that act as triggers, causing the flower to release 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...
when an insect arrives. There are now two varieties of this plant, with var. savannarum having been described in 2001. It has wider leaves and more limp branches than var. immaculata.
This plant grows in white- and yellow-sand Florida scrub
Florida scrub
Florida scrub is an endangered temperate coniferous forest ecoregion of the state of Florida in the United States. It is found on coastal and inland sand ridges and is characterized by a xeromorphic plant community dominated by shrubs and dwarf oaks. Scrub soils, a type of entisol, are derived...
habitat
Habitat
* Habitat , a place where a species lives and grows*Human habitat, a place where humans live, work or play** Space habitat, a space station intended as a permanent settlement...
. It can be found in openings and slightly shady areas where the wind or wildfire
Wildfire
A wildfire is any uncontrolled fire in combustible vegetation that occurs in the countryside or a wilderness area. Other names such as brush fire, bushfire, forest fire, desert fire, grass fire, hill fire, squirrel fire, vegetation fire, veldfire, and wilkjjofire may be used to describe the same...
has cleared a partial or total space in the canopy. This habitat is becoming ever more rare today as it is consumed for development; Florida's population is growing rapidly. Several known populations of this plant have been destroyed in the process. Remaining tracts of land are very fragmented
Habitat fragmentation
Habitat fragmentation as the name implies, describes the emergence of discontinuities in an organism's preferred environment , causing population fragmentation...
.
There are not many predators that tolerate the strong oils of this mint, so herbivory is not a serious problem. Mildew
Mildew
Mildew refers to certain kinds of molds or fungi.In Old English, it meant honeydew , and later came to mean mildew in the modern sense of mold or fungus....
affects the flowers sometimes, however, causing fruit destruction. Invasive plant species
Invasive species
"Invasive species", or invasive exotics, is a nomenclature term and categorization phrase used for flora and fauna, and for specific restoration-preservation processes in native habitats, with several definitions....
that threaten the habitat include Brazilian pepper (Schinus terebinthifolius), rosary pea (Abrus precatorius), Natal grass
Melinis repens
Melinis repens is a species of grass known by the common names rose Natal grass, or simply Natal grass, and Natal redtop. It is native to southern Africa but it is well known on other continents, including North America and Australia, as an introduced species and sometimes a noxious weed...
(Rhynchelytrum repens), and Guinea grass
Megathyrsus maximus
Megathyrsus maximus, known as Guinea Grass or Green Panic Grass in English, is a large perennial bunch grass that is native to Africa Palestine, and Yemen. It has been introduced in the tropics around the world. Due to its wide distribution, it has common names in a large number of languages and...
(Panicum maximum).
Some new populations of the species have been planted in areas that are protected, even though they are outside the known historical range of the plant.