Overall At-Risk Score: 75
Santalum spp. (L.); S. album, S. ellipticum, S. freycinetianum, S. haleakalae, S. involutum, S. paniculatum, S. salicifolium.
- Sandalwood (‘Iliahi)
- Indian Sandalwood (S. album)
- Coastal Sandalwood ‘Iliahialo’e (S. ellipticum)
- Forest Sandalwood Freycinet sandalwood (S. freycinetianum)
- Haleakalae Sandalwood (S. haleakalae)
- Involute Sandalwood (S. involutum)
- Hawai’i Sandalwood, Mountain Sandalwood (S. paniculatum)
- Willowleaf Sandalwood (S. salicifolium)
Santalacea (Sandalwood family)
Long-lived trees and perennial shrubs
Sandalwood trees produce clusters of small flowers, in a variety of colors, at the end of leafing twigs. A small number of these flower clusters turn into fruit that go on to become clusters of small, hard seeds surrounded by a thin fleshy skin. These are then ideally eaten by birds as a means of seed dispersal. It is important to note that Sandalwoods are dioecious and thus need both a “male” and “female” plant in order to reproduce.
Sandalwood seeds are very short-lived in storage and should be planted immediately to ensure viability.
All species listed above are native to the islands of Hawaii, except for Indian Sandalwood (S. album), which was introduced from India.
Each species of Sandalwood has adapted to survive in its own part of the Hawaiian islands, with their common names reflecting the general regions they’re located in. As a general rule, all sandalwoods are hemiparasitic, so they do best when able to pair themselves to another host plant or tree.
- Indian Sandalwood is native to Maritime Southeast Asia and does best in dry, sandy soil and forested areas. It grows from sea level to 700 meters (2,300 feet) and can be found in almost all islands in Hawaii.
- Coastal Sandalwood lives in dry regions such as lava plains and shrublands from sea level to as high as 950 meters (3,120 ft). They inhabit both the main 8 islands as well as the smaller islands to the northwest.
- Forest or Freycinet Sandalwood can thrive in almost any forested areas, regardless of water levels. It grows best at elevations of 250 to 950 meters (820 to 3,120 feet) and can be found in all of the main 8 islands except for Hawai’i Island (the largest island in the state).
- Haleakalae Sandalwood lives in shrublands from 1,900 to 2,700 meters (6,200 to 8,900 feet). It’s found exclusively around the volcano Haleakalā on the island of Maui, one of the 8 main islands of Hawaii.
- Mountain Sandalwood lives in dry forests from 450 to 2,550 meters (1480 to 8,370 feet) on several of the main islands of Hawaii.
Ability to Withstand Disturbance and Overharvest:
Being slow-growing trees, Sandalwoods are heavily impacted by logging and agricultural development.
Status of Endangered/Threatened:
Involute Sandalwood (S. involutum) and Lanaiense, a variety of Forest Sandalwood (S. freycinetianum), have already been officially recognized as endangered. Therefore UpS has added the remaining native species to the “At-Risk” list, in an effort to bring about stewardship of these living Hawaiian heirlooms that desperately need regulations that will provide guidelines to their management and protection.
S. freycinetianum is recognized as “Endangered”⁴, and both S. album and S. haleakalae are listed as “Vulnerable” by the IUCN Red List.
Part of Plant Used/Active Medicinal Compounds:
The wood and the oils from the wood are used in perfume scents and many different skincare products and have been popular for centuries through much of East Asia.
Vulnerability of Habitat/Changes of Habitat Quality and Availability:
These trees (excluding S. album) are endemic to the various island of Hawaii, meaning their possible habitat is incredibly limited. This creates an urgency in efforts to conserve these trees, as urban development, agriculture, and forestry continue to encroach on these small ecosystems. Invasive species that have been transported to the area such as various kinds of rats, as well as some plants, are also a major concern, as they take resources away from the Sandalwoods and limit how far they can expand.
Wild Harvesting Impact On Other Species:
Demand for the oil of Indian Sandalwood (S. album) combined with limited supply has led to the market expanding to include other Sandalwood species, particularly Hawaii’s native Sandalwood. Sandalwood is also an important plant for endemic bird species in Hawaii that rely on their fruits as a source of food.
Sandalwood is considered to be some of the most valuable wood in the world, and the oil’s use in medicine and cosmetics puts it at a high demand. It can also be difficult to farm efficiently, due to its hemiparasitic nature. Sandalwoods need other plants around them in order to survive long enough to be considered useful for oil production and are known to self-parasitize and attach onto other sandalwood trees. Regardless of this, efforts are still being made in places such as southern India to farm Sandalwoods to reduce their reliance on wild Sandalwoods.
Recommendations for Industrial and Home Use:
Luxury items derived from slow-growing lumber, like the oil of the Sandalwood trees, are often very unsustainably managed and have drastic impacts on the ecology of where these resources are being extracted. They are best avoided, or replaced with wood that is harvested more sustainably, whenever possible. Other plants, such as Amyris balsamifera and Amyris elemifera are both used as substitutions for sandalwood when used for cosmetics, perfumes, and soaps.
Articles of Interest:
- Elevitch, C. R., Abbott, I. A., & Leakey, R. R. (2006). Traditional trees of Pacific Islands: Their culture, environment, and use. Hōlualoa, Hawaiʻi: Permanent Agriculture Resources.
- Hawaiian Native Plant Propagation Database: Santalum freycinetianum. (n.d.). Retrieved from https://www.ctahr.hawaii.edu/hawnprop/plants/san-frey.htm
- Merlin, M., & Van Ravenswaay, D. (1990, April 9-11). The History of Human Impact on the Genus Santalum in Hawai‘i. Lecture presented at Symposium on Sandalwood in Hawaii, Honolulu, Hawaii.
- Native Plants Hawaii. Santalum ellipticum. Retrieved from http://nativeplants.hawaii.edu/plant/view/Santalum_ellipticum
- Native Plants Hawaii. Santalum freycinetianum. Retrieved from http://nativeplants.hawaii.edu/plant/view/Santalum_freycinetianum
- Pejhanmehr, M. & Adams, J. 2016. Santalum freycinetianum. The IUCN Red List of Threatened Species 2016: e.T62929A95817407. http://dx.doi.org/10.2305/IUCN.UK.2016-2.RLTS.T62929A95817407.en. Downloaded on 04 July 2019.
- United States Department of Agriculture. Plants Profile for Santalum (Sandalwood). Retrieved July 4, 2019, from https://plants.usda.gov/core/profile?symbol=SANTA
World Conservation Monitoring Centre 2016. Santalum haleakalae var. haleakalae. The IUCN Red List of Threatened Species 2016: e.T30783A91085891. http://dx.doi.org/10.2305/IUCN.UK.2016-1.RLTS.T30783A91085891.en. Downloaded on 04 July 2019.