Sapindus oahuensis
{{Short description|Species of tree}}
{{Speciesbox
|image = Sapindus oahuensis (5187914415).jpg
|status = VU
|status_system = IUCN2.3
|genus = Sapindus
|species = oahuensis
|authority = Hillebr. ex Radlk.{{GRIN | accessdate=2011-10-04}}
|synonyms = Sapindus lonomea H.St.John{{ITIS |id=28698 |taxon=Sapindus oahuensis |accessdate=2011-10-04}}
}}
Sapindus oahuensis is a species of tree in the soapberry family, Sapindaceae. It is endemic to Hawaii, where it is limited to Kaua{{okina}}i (Waimea Canyon) and O{{okina}}ahu (Wai{{okina}}anae and Ko{{okina}}olau Ranges). Its common names include Āulu,Little, E. L. and R. G. Skolmen. [http://www.ctahr.hawaii.edu/forestry/trees/CommonTreesHI/CFT_Sapindus_oahuensis.pdf Āulu, Sapindus oahuensis Hillebr.] Common Forest Trees of Hawaii (Native and Introduced). Agriculture Handbook no. 679. USDA Forest Service, 1989. Oahu soapberry, alulu, kaulu, and lonomea.
File:Sapindus oahuensis (6698129351).jpg
It can be found in dry and moist forest habitat at elevations of 200 to 2000 feet.{{cite web |url=http://www.ntbg.org/plants/plant_details.php?plantid=11902&rid=2160 |title=Sapindus oahuensis Hillebrand (Sapindaceae)|publisher=National Tropical Botanical Gardens |access-date=2009-11-13}}
Anatomy & Morphology
Āulu grows up to {{convert|18|m|ft|abbr=on}} tall with a trunk diameter of {{convert|0.5|m|ft|abbr=on}}. It has alternately arranged, hairless leaves which have simple blades, unlike its congener, the wingless soapberry (S. saponaria), which has compound leaves. The leaves are somewhat thick and green with a yellow midvein. They are up to 15 centimeters long. The inflorescence is a panicle of many greenish yellow, bell-shaped male and female flowers. The fruit is a shiny, leathery berry roughly 2 centimeters long, containing one large black seed.
The inflorescence is a panicle of many greenish yellow, bell shaped male and female flowers. They bloom during the spring, summer, and winter.{{Cite web |title=Native Plants Hawaii - Viewing Plant : Sapindus oahuensis |url=http://nativeplants.hawaii.edu/plant/view/Sapindus_oahuensis/ |access-date=2024-12-10 |website=nativeplants.hawaii.edu}} The flowers grow in clusters from the bases of the leaf stems .{{Cite web |title=Sapindus oahuensis (Lonomea) |url=https://www.ctahr.hawaii.edu/hawnprop/plants/sap-oahu.htm |access-date=2024-12-10 |website=www.ctahr.hawaii.edu}} The fruit is a shiny, leathery berry roughly 2 cetimeters longs, containing one black seed. However, the fruits are not edible.{{Cite web |title=Native Hawaiian Garden (7722) - Lonomea |url=https://www.nativehawaiiangarden.org/flowering-plants/lonomea |access-date=2024-12-10 |website=www.nativehawaiiangarden.org |language=en-US}} The wood is hard and light brown with gray-to-white bark. Yellow-brown fuzz coats the younger branches.{{Cite web |title=Lonomea |url=https://dlnr.hawaii.gov/forestry/plants/lonomea/ |access-date=2024-12-10 |website=dlnr.hawaii.gov |language=en}} Balladyna velutina is a common fungus which grows on Sapindus oahunesis . This fungus appears as a powdery white mildew.{{Cite journal |last=Goos |first=R. D. |last2=Uecker |first2=F. A. |date=1992 |title=New Species and Additional Records of Fungi from Hawaii |url=https://www.jstor.org/stable/3760184 |journal=Mycologia |volume=84 |issue=3 |pages=322–328 |doi=10.2307/3760184 |issn=0027-5514}}
Distribution & Habitat
It can be found in dry and moist forest habitat at elevations of 200 to 2000 feet. It is possible that the Sapindus oahunesis arrived in Hawaiʻi by floating in the water because the fruit have trapped air pockets which allow them to float . Sapindus oahunesis tend to inhabit semi-deciduous forests that are dry.{{Cite journal |last=Hatheway |first=William H. |date=1952 |title=Composition of Certain Native Dry Forests: Mokuleia, Oahu, T.H. |url=https://esajournals.onlinelibrary.wiley.com/doi/10.2307/1943515 |journal=Ecological Monographs |language=en |volume=22 |issue=2 |pages=153–168 |doi=10.2307/1943515 |issn=1557-7015}}
Human & Cultural Significance
Early Hawaiians used the hard blackish seeds for medicinal purposes and to string permanent lei. The hardwood was used to make spears . Today this tree is used for itʻs fragrance, to provide privacy/shade, woodwork, or as a windbreak.{{Cite web |title=Sapindus oahuensis |url=https://plantpono.org/pono-plants/sapindus-oahuensis/ |access-date=2024-12-10 |website=Plant Pono |language=en-US}} It may also be used to wash hair or clothes by cutting up the fruits and mixing them with water .
It is tolerant to drought and windy conditions. Sapindus oahunesis are also important in providing habitat for native bird species, such as the ʻelepaio .{{Cite journal |last=Vanderwerf |first=Eric A. |date=2009 |title=Importance of Nest Predation by Alien Rodents and Avian Poxvirus in Conservation of Oahu Elepaio |url=https://www.jstor.org/stable/40208434 |journal=The Journal of Wildlife Management |volume=73 |issue=5 |pages=737–746 |issn=0022-541X}}
Conservation
In 1998, Sapindus oahunesis was assessed for the IUCN Red List of Threatened Species and was listed as Vulnerable under criteria A1ce.{{Cite web |date=1 January 1998 |title=Sapnidus oahunesis |url=https://www.iucnredlist.org/species/31364/9622279 |access-date=1 December 2024 |website=IUCN Red List of Threatened Species}} As of November 2024, it is considered imperiled/vulnerable .{{Cite web |title=NatureServe Explorer 2.0 |url=https://explorer.natureserve.org/Taxon/ELEMENT_GLOBAL.2.149829/Sapindus_oahuensis |access-date=2024-12-10 |website=explorer.natureserve.org}}
Disease & Pests
The most common pests of the Sapindis oahunesis is the black twigboreers and false powderpost beeetles which bore into the wood. It is best to remove any dead branches to minimize their impact. Sometimes, the smaller leaves are chewed by Chinese rose beetles. It is recommended to hand pick the beetles off the plant every few weeks during the night time or trying rose beetle traps . Occasionally, whiteflies will infest the underside of the leaves, which may be treated with an at home insecticidal soap.
References
{{Reflist}}
External links
- {{Commons category-inline|Sapindus oahuensis|Sapindus oahuensis}}
- {{Wikispecies-inline|Sapindus oahuensis|Sapindus oahuensis}}
- {{cite web |url=http://www2.hawaii.edu/~eherring/hawnprop/sap-oahu.htm |title=Sapindus oahuensis |work=Hawaiian Native Plant Propagation Database |publisher=University of Hawaiʻi at Mānoa }}
{{Taxonbar|from=Q5464177}}
Category:Endemic flora of Hawaii