Galactia smallii
Encyclopedia
Galactia smallii is a rare species of flowering plant in the legume family
known by the common name Small's milkpea. It is endemic to Florida
, where it is known only from a few small patches of remaining habitat in Miami-Dade County
. It is threatened by the destruction
and inadequate management of its habitat. It was federally listed as an endangered species
of the United States in 1985.
This plant is a creeping or climbing vine
with gray-haired stems reaching up to 2 meters long. The shaggy hairs on the stem nodes may be up to 8 millimeters long. Each leaf is compound, made up of three hairy leaflets that measure 1 to 2 centimeters long. The inflorescence
produces 1 to 5 pea flowers which are just over a centimeter long and pink to lavender in color. The flowers are pollinated by the Cassius blue butterfly
(Leptotes cassius theonus) and other insects. The fruit is a hairy legume pod 3 or 4 centimeters long and a few millimeters wide.
This species grows in Florida's pine rockland
habitat, an increasingly rare type of ecosystem
dominated
by the slash pine (Pinus elliottii). The trees are narrow and the canopy is open, providing sunlight to the understory. Among the pines are over 100 species of trees, including many palms, and a diverse array of herbs, including many rare and endemic species. The habitat is maintained by a natural fire regime
of periodic wildfire
which prevents the succession
of the pine rockland to a hammock
ecosystem. Fire clears overgrown tall and woody vegetation to maintain the characteristic open canopy. Less than 2% of the pine rocklands of Florida remain today.
When this plant was added to the endangered species list it was known from only two places near Homestead, Florida
. The habitat was being rapidly consumed and converted to residential tracts in the Miami metropolitan area
. Remaining fragmented
strips of the habitat were becoming degraded, primarily by the practice of fire suppression. The area, which would normally burn every 3 to 7 years, was becoming overgrown and the habitat was changing from pine rockland to hammock. In the absence of fire the open canopy fills in with brush and mature trees and Small's milkpea cannot tolerate the shade.
Appropriate land management
in the pine rocklands involves controlled burn
s to mimic the natural pattern. Fire also helps to prevent the encroachment of invasive plants
. One of the worst offenders is Natal grass
(Melinis repens).
The plant is present at eight sites on public land and an unknown number of sites on private property. The County of Miami-Dade has purchased some tracts of land that contain the plant for the purpose of managing and conserving them. The largest population is located on public, county-owned land near the Homestead Joint Air Reserve Base, and negotiations are underway to develop a plan for the land.
Fabaceae
The Fabaceae or Leguminosae, commonly known as the legume, pea, or bean family, is a large and economically important family of flowering plants. The group is the third largest land plant family, behind only the Orchidaceae and Asteraceae, with 730 genera and over 19,400 species...
known by the common name Small's milkpea. 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...
, where it is known only from a few small patches of remaining habitat in Miami-Dade County
Miami-Dade County, Florida
Miami-Dade County is a county located in the southeastern part of the state of Florida. As of 2010 U.S. Census, the county had a population of 2,496,435, making it the most populous county in Florida and the eighth-most populous county in the United States...
. It is threatened by the destruction
Habitat destruction
Habitat destruction is the process in which natural habitat is rendered functionally unable to support the species present. In this process, the organisms that previously used the site are displaced or destroyed, reducing biodiversity. Habitat destruction by human activity mainly for the purpose of...
and inadequate management of its habitat. It 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...
of the United States in 1985.
This plant is a creeping or climbing vine
Vine
A vine in the narrowest sense is the grapevine , but more generally it can refer to any plant with a growth habit of trailing or scandent, that is to say climbing, stems or runners...
with gray-haired stems reaching up to 2 meters long. The shaggy hairs on the stem nodes may be up to 8 millimeters long. Each leaf is compound, made up of three hairy leaflets that measure 1 to 2 centimeters long. The inflorescence
Inflorescence
An inflorescence is a group or cluster of flowers arranged on a stem that is composed of a main branch or a complicated arrangement of branches. Strictly, it is the part of the shoot of seed plants where flowers are formed and which is accordingly modified...
produces 1 to 5 pea flowers which are just over a centimeter long and pink to lavender in color. The flowers are pollinated by the Cassius blue butterfly
Leptotes cassius
Leptotes cassius, commonly known as the Cassius Blue or Tropical Striped Blue, is a butterfly of the Lycaenidae family. It is found in Florida and the Keys, Texas south through the Caribbean, Mexico, and Central America to South America...
(Leptotes cassius theonus) and other insects. The fruit is a hairy legume pod 3 or 4 centimeters long and a few millimeters wide.
This species grows in Florida's pine rockland
South Florida rocklands
The South Florida rocklands ecoregion, in the Tropical and subtropical moist broadleaf forests Biome, occurring in southern Florida and the Florida Keys in the United States, where they would naturally cover an area of . These forests form on limestone outcroppings with very thin soil; the higher...
habitat, an increasingly rare type of ecosystem
Ecosystem
An ecosystem is a biological environment consisting of all the organisms living in a particular area, as well as all the nonliving , physical components of the environment with which the organisms interact, such as air, soil, water and sunlight....
dominated
Dominant species
Dominant species may mean:*Dominant species , one of a small number of species which dominate in an ecological community*Dominant Species by Michael E. Marks*Dominant Species...
by the slash pine (Pinus elliottii). The trees are narrow and the canopy is open, providing sunlight to the understory. Among the pines are over 100 species of trees, including many palms, and a diverse array of herbs, including many rare and endemic species. The habitat is maintained by a natural fire regime
Fire regime
A fire regime is the pattern, frequency and intensity of the bushfires and wildfires that prevails in an area. It is an integral part of fire ecology, and renewal for certain types of ecosystems. If fires are too frequent, plants may be killed before they have matured, or before they have set...
of periodic 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...
which prevents the succession
Ecological succession
Ecological succession, is the phenomenon or process by which a community progressively transforms itself until a stable community is formed. It is a fundamental concept in ecology, and refers to more or less predictable and orderly changes in the composition or structure of an ecological community...
of the pine rockland to a hammock
Hammock (ecology)
Hammocks are dense stands of hardwood trees that grow on natural rises of only a few inches higher than surrounding marshland that is otherwise too wet to support them. Hammocks are distinctive in that they are formed gradually over thousands of years rising in a wet area through the deposits of...
ecosystem. Fire clears overgrown tall and woody vegetation to maintain the characteristic open canopy. Less than 2% of the pine rocklands of Florida remain today.
When this plant was added to the endangered species list it was known from only two places near Homestead, Florida
Homestead, Florida
Homestead is a city in Miami-Dade County, Florida, United States nestled between Biscayne National Park to the east and Everglades National Park to the west. Homestead is primarily a Miami suburb and a major agricultural area....
. The habitat was being rapidly consumed and converted to residential tracts in the Miami metropolitan area
South Florida metropolitan area
The South Florida metropolitan area, also known as the Miami metropolitan area, and designated the Miami–Fort Lauderdale–Pompano Beach, FL Metropolitan Statistical Area by the U.S...
. Remaining fragmented
Habitat fragmentation
Habitat fragmentation as the name implies, describes the emergence of discontinuities in an organism's preferred environment , causing population fragmentation...
strips of the habitat were becoming degraded, primarily by the practice of fire suppression. The area, which would normally burn every 3 to 7 years, was becoming overgrown and the habitat was changing from pine rockland to hammock. In the absence of fire the open canopy fills in with brush and mature trees and Small's milkpea cannot tolerate the shade.
Appropriate land management
Land management
Land management is the process of managing the use and development of land resources. Land resources are used for a variety of purposes which may include organic agriculture, reforestation, water resource management and eco-tourism projects.-See also:*Sustainable land management*Acreage...
in the pine rocklands involves controlled burn
Controlled burn
Controlled or prescribed burning, also known as hazard reduction burning or Swailing is a technique sometimes used in forest management, farming, prairie restoration or greenhouse gas abatement. Fire is a natural part of both forest and grassland ecology and controlled fire can be a tool for...
s to mimic the natural pattern. Fire also helps to prevent the encroachment of invasive plants
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....
. One of the worst offenders is 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...
(Melinis repens).
The plant is present at eight sites on public land and an unknown number of sites on private property. The County of Miami-Dade has purchased some tracts of land that contain the plant for the purpose of managing and conserving them. The largest population is located on public, county-owned land near the Homestead Joint Air Reserve Base, and negotiations are underway to develop a plan for the land.