''Serianthes nelsonii'' is a large tree endemic to Guam and

Rota Rota or ROTA may refer to: Places * Rota (island), in the Marianas archipelago * Rota (volcano), in Nicaragua * Rota, Andalusia, a town in Andalusia, Spain * Naval Station Rota, Spain People * Rota (surname), a surname (including a list of peop ...

of the

Mariana Islands The Mariana Islands (; also the Marianas; in Chamorro: ''Manislan Mariånas'') are a crescent-shaped archipelago comprising the summits of fifteen longitudinally oriented, mostly dormant volcanic mountains in the northwestern Pacific Ocean, betw ...

. Only one mature tree exists on Guam, while 121 mature trees have been identified on Rota since 1984.''Serianthes nelsonii'', poster by Agricultural Experiment Station, College of Agriculture and Life Sciences, University of Guam The tree is found in limestone forests in Rota and Guam. It has bipinnately compound

leaves A leaf (plural, : leaves) is any of the principal appendages of a vascular plant plant stem, stem, usually borne laterally aboveground and specialized for photosynthesis. Leaves are collectively called foliage, as in "autumn foliage", wh ...

and brush-like flowers with long pinkish filaments. Seedpods contain one to seven smooth brown seeds.

Name

There are three local names for ''S. nelsonii''. On Guam, it is known as hayun lågu, meaning "northern tree" or "foreign tree", referring to Rota, which is located north of Guam. The common name on Rota is trongkon guåfi, meaning "fire tree". Another name on Rota is trongkon fi'a may have originated in a region on Rota called Fia. Alternatively, "fi'a" may have derived from the Chamorro pronunciation of "fire", from "guåfi". The species was named "nelsonii" by E.D. Merrill in 1919 to honor Peter Nelson of the Guam Department of Agriculture, the discoverer of the plant.

Conservation

''Serianthes nelsonii'' was declared an endangered plant in 1987 and was assessed as critically endangered in 1998 and again in 2017. The University of Guam began a program to save the plant in 1998 with the help of numerous other agencies. ''S. nelsonii'' seedlings are being raised on protected lands for transplantation back into the wilds of Guam. On Rota, the Department of Lands and Natural Resource is monitoring the plant population and growing seedlings in a plant nursery. In 2019, the single remaining mature tree on Guam was diagnosed with heart rot, raising concerns about if it could survive the next tropical storms. A total of 18 trees exist on Guam. In June 2019, the

Legislature of Guam The Legislature of Guam ( ch, Liheslaturan Guåhan) is the law-making body for the United States territory of Guam. The unicameral legislative branch consists of fifteen senators, each serving for a two-year term. All members of the legislature a ...

passed a resolution to urging a halt to planned military buildup and construction until the impact to ''S. nelsonii'' could be investigated. Insufficient regeneration is blamed for the decline of the population. Possible causes include insect predation on seeds and predation on seedlings by invasive species, invasive ungulates and mealybugs. The subpopulation on Rota is expected to decline as older trees die.

References

External links

* * {{Taxonbar, from=Q548581 Serianthes, nelsonii Critically endangered plants Flora of the Mariana Islands Taxa named by Elmer Drew Merrill