{{Short description|Mountain subrange in Puerto Rico}} {{Infobox mountain | name = Sierra de Luquillo | image = Clearer view of Yunque's top from the Yokahú Tower.jpg | image_caption = El Yunque | map_caption = Location of the Sierra de Luquillo in Puerto Rico | elevation_ft = 3,526 | highest = El Toro | coordinates = {{Coord|18|16|20|N|65|49|45|W|type:mountain_region:US:PR|display=inline}} | location = Puerto Rico | range_coordinates = {{Coord|type:mountain_region:US:PR|format=dms|display=inline,title}} | parent = Cordillera Central }} The '''Sierra de Luquillo''' (English: "Luquillo Mountains") is a steep-sided, high-precipitation, and deeply-forested subrange of the Cordillera Central mountain range in the main island of Puerto Rico. Separated from the southeastern Sierra de Cayey subrange by the Caguas Valley, it is concentrated from west to east in the municipalities of Rio Grande, Luquillo, and Naguabo in the northeastern region of the island. The summit of the mountain range is El Toro at 3,526 ft. (1,075 m), and its most recognizable peak is El Yunque at 3,461 ft. (1,054 m).<ref>{{Cite web |title=Reassessing rainfall in the Luquillo Mountains, Puerto Rico: Local and global ecohydrological implications |url=https://www.researchgate.net/figure/Map-of-Luquillo-Mountains-Puerto-Rico-showing-elevation-topography-and-watersheds_fig1_318287454 |access-date=3 September 2024 |website=ResearchGate }}</ref> As the location of El Yunque National Forest, the Sierra de Luquillo is a popular destination among domestic and foreign tourists. [[File:Topography of the Commonwealth of Puerto Rico by USDA.jpg|thumb|300px|Topographical map of Puerto Rico with the Sierra de Luquillo in the northeast]]
Along with the eponymous main subrange of ''Cordillera Central'' and the Sierra de Cayey, the Luquillo mountain range is one of three subranges of the Cordillera Central. However, although a subrange of the Cordillera Central, the Sierra de Luquillo is occasionally considered to be different from the rest of the central mountain range, as it is separated from it by the Caguas Valley and the Rio Grande de Loíza basin.
== Geography == The mountains of the Sierra de Luquillo were formed by tectonic activity some 37 to 28 million years ago, the island being on the junction between the North American Plate and the Caribbean Plate.<ref name=NASA>{{cite web |url=https://earthobservatory.nasa.gov/images/8453/luquillo-mountains-puerto-rico |title=Luquillo Mountains, Puerto Rico |work=Earth Observatory |date=4 February 2008 |publisher=NASA |access-date=27 March 2019 }}</ref> The main rock types are pyroclastic rocks, quartzdiorite and contact metamorphic hornfels, with some outcrops of alluvium, basalt and mafic rocks. Nine rivers have their sources in the mountains, flowing downward through steep, rocky and boulder-strewed channels before reach the coastal plains.<ref>{{cite web |url=https://criticalzone.org/luquillo/infrastructure/field-area/northeastern-puerto-rico-and-the-luquillo-mountains/ |title=Northeastern Puerto Rico and the Luquillo Mountains |publisher=The Luquillo Critical Zone Observatory |access-date=27 March 2019 }}</ref> Easterly winds off the Atlantic Ocean rise and cool as they pass over the mountains, and the ensuing heavy precipitation brings an annual rainfall of {{cvt|5000|mm|in|-2}} on the ridge. The lower slopes are less wet, but the summits are immersed in clouds most of the year.<ref name=USDA>{{cite web |url=https://www.fs.fed.us/research/publications/efr/efr_wo1.pdf |title=Luquillo Experimental Forest: Research History and Opportunities |author=Harris, N.L.; Lugo, A.E.; Brown, S.; Heartsill Scalley, T. (Eds.) |date=May 2012 |publisher=USDA, US Forest Service |access-date=27 March 2019 |archive-date=30 May 2017 |archive-url=https://web.archive.org/web/20170530091913/https://www.fs.fed.us/research/publications/efr/efr_wo1.pdf |url-status=live }}</ref>
The Sierra de Luquillo consists of a series of summits linked by a horseshoe-shaped ridge. Running from west to east, some of the peaks include El Toro, El Cacique and El Yunque, joined by a ridge known as ''Cuchilla el Duque'' to Pico del Oeste and Pico del Este.<ref>{{cite journal |author1=Murphy, Sheila F. |author2=Stallard, Robert F. |author3=Scholl, Martha A. |author4=González, Grizelle |author-link4=Grizelle González |author5=Torres-Sánchez, Angel J. |year=2017 |title=Reassessing rainfall in the Luquillo Mountains, Puerto Rico: Local and global ecohydrological implications |journal=PLOS ONE |volume=12 |issue=7 |article-number=e0180987 |doi=10.1371/journal.pone.0180987 |pmid=28686734 |pmc=5501619 |bibcode=2017PLoSO..1280987M |doi-access=free }}</ref>
== Mountains == The highest summits of the Sierra de Luquillo are the following:<ref>{{Cite web |title=Puerto Rico mountains list {{!}} peakery |url=https://peakery.com/region/puerto-rico-mountains/peaks/#order=elevation&page=1 |access-date=8 September 2021 |website=peakery.com |archive-date=8 September 2021 |archive-url=https://web.archive.org/web/20210908060915/https://peakery.com/region/puerto-rico-mountains/peaks/#order=elevation&page=1 |url-status=live }}</ref>
# El Toro - 3,526 ft. (1,075 m) # El Yunque - 3,483 ft. (1,062 m) # Pico del Este - 3,408 ft. (1,038 m) # Pico del Oeste - 3,339 ft. (1,017 m) # El Cacique - 3,326 ft. (1,013 m) # Roca El Yunque - 3,270 ft. (996 m) # Los Picachos - 3,041 ft. (926 m) # Mount Britton - 3,011 ft. (917 m) # Cerro La Mina - 2,919 ft. (889 m)
== Flora and fauna == thumb|El Yunque from Torre Britton
The mountains are covered with rainforest, much of it in the El Yunque National Forest. About 240 species of native tree have been recorded in the forest, 88 species being considered rare and about 25 species being found nowhere else in the world. There are about 150 species of fern, and on the trees grow many epiphytes, including about 50 species of orchid.<ref name=Land>{{cite web |url=https://www.fs.usda.gov/land/elyunque/landmanagement |archive-url=https://web.archive.org/web/20111211024429/http://www.fs.usda.gov/land/elyunque/landmanagement |archive-date=December 11, 2011 |title=Land & Resources Management |work=El Yunque National Forest |publisher=USDA |access-date=27 March 2019 }}</ref> Common trees of the Sierra de Luquillo include ''Cyathea arborea'', ''Prestoea montana'', ''Cecropia peltata'', and ''Ocotea'' species while ''Weinmannia pinnata'', ''Brunellia comocladifolia'', and ''Podocarpus coriaceus'' are found in the cloud forests of the highest peaks.<ref>{{cite book |url=https://books.google.com/books?id=DRl_RhheUhQC |title=Terrestrial Ecoregions of North America: a Conservation Assessment |first=D. |last=Olson |editor=Taylor H. Ricketts |publisher=Island Press |year=1999 |isbn=978-1-55963-722-0 |page=152 }}</ref> These dwarf forests occur above the cumulus cloud bases and contain low, dense, species-poor vegetation cover known as elfin or pigmy forest.<ref>{{cite book |author=Weaver, Peter L. |chapter=The Colorado and Dwarf Forests of Puerto Rico's Luquillo Mountains |year=1995 |title=Tropical Forests: Management and Ecology |series=Ecological Studies |volume=112 |pages=109–141 |doi=10.1007/978-1-4612-2498-3_5 |isbn=978-1-4612-2498-3 }}</ref> A research study found that between 1936 and 1988, there were 46 landslides associated with heavy rain in the upper regions of the mountains, and these created gaps that allowed the seeds of pioneering tree species to germinate and ferns such as ''Dicranopteris pectitnata'' to proliferate.<ref>{{cite journal |last1=Guariguata |first1=M.R. |title=Landslide disturbance and forest regeneration in the Upper Luquillo mountains of Puerto Rico |journal=Journal of Ecology |date=1990 |volume=78 |issue=3 |pages=814–832 |doi=10.2307/2260901 |jstor=2260901 |bibcode=1990JEcol..78..814G }}</ref> The forest recovers more quickly after a natural disaster, such as a tropical cyclone, than it does after human activities such as logging, charcoal burning, coffee production or agriculture.<ref name=NASA/>
Some 127 species of terrestrial vertebrate have been recorded in the forest,<ref name=Land/> including some rarities and some species endemic to Puerto Rico. The Puerto Rican amazon is critically endangered with fewer than 100 left in the wild. The Puerto Rican broad-winged hawk and Puerto Rican sharp-shinned hawk are both very rare. Many birds visit the island during their annual migrations. The Puerto Rican boa inhabits the lower slopes of the mountains, about 14 species of lizard are found in the forest and 13 species of small tree frogs known as coquí live in the canopy and are endemic to the island.<ref>{{cite web |url=http://www.fs.usda.gov/r08/elyunque |title=Natural Resources: Endangered and Threatened Species |work=El Yunque National Forest |publisher=USDA |access-date=27 March 2019 }}</ref>
== References == {{Reflist}}
== Further reading == * {{cite book |last1=Weaver |first1=Peter L. |title=La sierra de Luquillo: los recursos forestales y su historia |publisher=U.S. Department of Agriculture |url=https://www.fs.usda.gov/Internet/FSE_DOCUMENTS/fseprd690952.pdf |archive-url=https://web.archive.org/web/20210909010905/https://www.fs.usda.gov/Internet/FSE_DOCUMENTS/fseprd690952.pdf |archive-date=September 9, 2021 |year=2012 |access-date=3 January 2023 }}
== External links == * {{Commons category-inline}}
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Category:Mountain ranges of Puerto Rico Category:Geography of Puerto Rico Category:Canóvanas, Puerto Rico Category:Carolina, Puerto Rico Category:Ceiba, Puerto Rico Category:Fajardo, Puerto Rico Category:Fajardo metropolitan area Category:Gurabo, Puerto Rico Category:Juncos, Puerto Rico Category:Las Piedras, Puerto Rico Category:Luquillo, Puerto Rico Category:Naguabo, Puerto Rico Category:Río Grande, Puerto Rico Category:Mountain ranges of the Caribbean