Platanthera holochila
Encyclopedia
Platanthera holochila is a rare species of orchid known by the common name Hawaii bog orchid. It is endemic to Hawaii
. It is a federally listed endangered species
of the United States.
When the orchid was added to the Endangered Species List in 1996 there were fewer than 35 individuals remaining, divided amongst small populations located on the islands of Kauai
, Maui
, and Molokai
. It has been extirpated
from Oahu
. By 2009 there were three populations for a total of 26 plants. There is only one plant remaining on Kauai and one on Maui, but neither have been observed recently. Hurricane Iniki
destroyed most of the Kauai population in 1992. The largest population, located on Molokai, is surrounded by a fence for protection from feral pigs, a main threat to the survival of the species. Other threats include damage to the habitat by cattle and the invasion
of introduced species
of plants such as glory bush (Tibouchina herbacea), Koster's curse
(Clidemia hirta), and Maui pamakani
(Ageratina adenophora).
This plant grows from a tuber
and produces an erect stem up to 60 centimeters tall. The yellow-green flowers are borne in erect spikes. Many aspects of the plant's life cycle
are unknown, including its mode of reproduction, its longevity
, and limiting factor
s. This is one of three endemic orchid species in Hawaii, and the rarest of the three. It grows in moist and wet forests and bog
s, on ridges, and in the subalpine zone on lava
substrates.
Conservation efforts include outplanting: planting propagated
individuals in appropriate habitat. Research on the propagation of the species is continuing. It is difficult to grow in the nursery. The seeds only germinate
in darkness. The plant will only grow in the presence of a mycorrhizal fungus
. Without the symbiotic relationship with the fungus the plant will not grow successfully. When outplanting cultivated plantlets, care must be taken to place them next to established plants that have already associated with the fungus.
Hawaii
Hawaii is the newest of the 50 U.S. states , and is the only U.S. state made up entirely of islands. It is the northernmost island group in Polynesia, occupying most of an archipelago in the central Pacific Ocean, southwest of the continental United States, southeast of Japan, and northeast of...
. It is a federally listed 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.
When the orchid was added to the Endangered Species List in 1996 there were fewer than 35 individuals remaining, divided amongst small populations located on the islands of Kauai
Kauai
Kauai or Kauai, known as Tauai in the ancient Kaua'i dialect, is geologically the oldest of the main Hawaiian Islands. With an area of , it is the fourth largest of the main islands in the Hawaiian archipelago, and the 21st largest island in the United States. Known also as the "Garden Isle",...
, Maui
Maui
The island of Maui is the second-largest of the Hawaiian Islands at and is the 17th largest island in the United States. Maui is part of the state of Hawaii and is the largest of Maui County's four islands, bigger than Lānai, Kahoolawe, and Molokai. In 2010, Maui had a population of 144,444,...
, and Molokai
Molokai
Molokai or Molokai is an island in the Hawaiian archipelago. It is 38 by 10 miles in size with a land area of , making it the fifth largest of the main Hawaiian Islands and the 27th largest island in the United States. It lies east of Oahu across the 25-mile wide Kaiwi Channel and north of...
. It has been extirpated
Local extinction
Local extinction, also known as extirpation, is the condition of a species which ceases to exist in the chosen geographic area of study, though it still exists elsewhere...
from Oahu
Oahu
Oahu or Oahu , known as "The Gathering Place", is the third largest of the Hawaiian Islands and most populous of the islands in the U.S. state of Hawaii. The state capital Honolulu is located on the southeast coast...
. By 2009 there were three populations for a total of 26 plants. There is only one plant remaining on Kauai and one on Maui, but neither have been observed recently. Hurricane Iniki
Hurricane Iniki
Hurricane Iniki was the most powerful hurricane to strike the U.S. state of Hawaii in recorded history. Forming on September 5 during the strong El Niño of 1991–1994, Iniki was one of eleven Central Pacific tropical cyclones during the 1992 season. It attained tropical storm status on...
destroyed most of the Kauai population in 1992. The largest population, located on Molokai, is surrounded by a fence for protection from feral pigs, a main threat to the survival of the species. Other threats include damage to the habitat by cattle and the invasion
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....
of introduced species
Introduced species
An introduced species — or neozoon, alien, exotic, non-indigenous, or non-native species, or simply an introduction, is a species living outside its indigenous or native distributional range, and has arrived in an ecosystem or plant community by human activity, either deliberate or accidental...
of plants such as glory bush (Tibouchina herbacea), Koster's curse
Clidemia hirta
Clidemia hirta, commonly called soapbush or Koster's Curse, is a perennial shrub.It is an invasive plant species in many tropical regions of the world, creating serious damage.-Distribution:...
(Clidemia hirta), and Maui pamakani
Ageratina adenophora
Ageratina adenophora is a species of flowering plant in the daisy family known by many common names, including eupatory, sticky snakeroot, crofton weed, and Mexican devil.- Description :...
(Ageratina adenophora).
This plant grows from a tuber
Tuber
Tubers are various types of modified plant structures that are enlarged to store nutrients. They are used by plants to survive the winter or dry months and provide energy and nutrients for regrowth during the next growing season and they are a means of asexual reproduction...
and produces an erect stem up to 60 centimeters tall. The yellow-green flowers are borne in erect spikes. Many aspects of the plant's life cycle
Biological life cycle
A life cycle is a period involving all different generations of a species succeeding each other through means of reproduction, whether through asexual reproduction or sexual reproduction...
are unknown, including its mode of reproduction, its longevity
Longevity
The word "longevity" is sometimes used as a synonym for "life expectancy" in demography or known as "long life", especially when it concerns someone or something lasting longer than expected ....
, and limiting factor
Limiting factor
A limiting factor or limiting resource is a factor that controls a process, such as organism growth or species population, size, or distribution. The availability of food, predation pressure, or availability of shelter are examples of factors that could be limiting for an organism...
s. This is one of three endemic orchid species in Hawaii, and the rarest of the three. It grows in moist and wet forests and bog
Bog
A bog, quagmire or mire is a wetland that accumulates acidic peat, a deposit of dead plant material—often mosses or, in Arctic climates, lichens....
s, on ridges, and in the subalpine zone on lava
Lava
Lava refers both to molten rock expelled by a volcano during an eruption and the resulting rock after solidification and cooling. This molten rock is formed in the interior of some planets, including Earth, and some of their satellites. When first erupted from a volcanic vent, lava is a liquid at...
substrates.
Conservation efforts include outplanting: planting propagated
Plant propagation
Plant propagation is the process of creating new plants from a variety of sources: seeds, cuttings, bulbs and other plant parts. Plant propagation can also refer to the artificial or natural dispersal of plants.-Sexual propagation :...
individuals in appropriate habitat. Research on the propagation of the species is continuing. It is difficult to grow in the nursery. The seeds only germinate
Germination
Germination is the process in which a plant or fungus emerges from a seed or spore, respectively, and begins growth. The most common example of germination is the sprouting of a seedling from a seed of an angiosperm or gymnosperm. However the growth of a sporeling from a spore, for example the...
in darkness. The plant will only grow in the presence of a mycorrhizal fungus
Fungus
A fungus is a member of a large group of eukaryotic organisms that includes microorganisms such as yeasts and molds , as well as the more familiar mushrooms. These organisms are classified as a kingdom, Fungi, which is separate from plants, animals, and bacteria...
. Without the symbiotic relationship with the fungus the plant will not grow successfully. When outplanting cultivated plantlets, care must be taken to place them next to established plants that have already associated with the fungus.