A Gift fit for a King: The Benefits of Boswellia Carteri or Frankincense Hydrosol and Resin
This article originally appeared in the NAHA Journal (Winter 2019.4) and it is re-published here according to the NAHA Writer Guidelines 2019-20 copyright statement.
Boswellia carterii Hydrosol and Resin: Ceremonial and Therapeutic Uses
Many people are familiar with frankincense in conjunction with the story of three wise men bearing gifts for Jesus. “When they saw the star, they were overjoyed. On coming to the house they saw the child with his mother Mary, and they bowed down and worshiped him. Then they opened their treasures and presented him with gifts of gold, frankincense, and myrrh.1
Frankincense resin was a luxurious gift worthy of a king or deity in ancient times and prized by the Greeks, Romans, Egyptians, Israelites, and other cultures for religious ceremonies and burial rituals.2
Naturalist George Birdwood described the sacredness of frankincense resin as it was used in the Hebrew temple. “Stacte, and onycha, galbanum, with pure frankincense were the sweet spices of which the pure and holy perfume…was made… which was offered every morning and evening, on the Alter of Incense… set in the Holy Place.”
“It was death for the priests to make the sacred incense for themselves… or for any one but the priests… to offer it, or to burn strange incense upon the Golden Altar.” 3
Frankincense has a rich history of trade and use from beauty treatments to sacred rituals.
As I write this I think of the Boswellia carterii resin or “tears” I have in my workspace that I use to infuse into carrier oils to make salves and can burn as incense and feel privileged to partake of this botanical treasure once reserved for kings, deity, and priests.
And although the availability of Boswellia resin and products derived from it are no longer limited to royalty, priests, and the like, it is nonetheless an exquisite gift to used with care and respect, especially since some species are considered “near threatened”. Although more readily available to many, there is nonetheless still something so regal, sacred, and even mysterious about frankincense.
Boswellia: Botanical Treasure, Botanical Mystery
In the aromatherapy community Boswellia carterii or carteri is commonly noted as the source of the hydrosol, while B. carterii or carteri, B. Sacra, B.frereana, and B. papyrifera resins are listed as sources for the essential oil. Powdered B. serrata resin is typically used an herb and can be found in capsule form.
As I scour literature concerning the botany Boswellia I have become entangled in a bit of a botanical mystery.
Is B.carterii simply a synonym for B. sacra or a distinct species? Were botanists and naturalists such as Frank Hepper and Théodore Monod correct in asserting that B. sacra is a distinct species native to Arabia while B. carterii is a distinct species native to Somalia and Somoliland*? 3 Or are the trees simply variants of the same species, namely B. sacra, responding to differences in environment as Botanist M.Thulin and Agriculture professor A.M. Warfa suggest? 4 Let’s look a little closer at this beautiful and mysterious genus.
Searching for Clues: Who’s Who in the World of Boswellia?
If you search for frankincense hydrosol the species typically used to create is listed as B. carterii. However on plant database sites the species is often listed as B. carteri with one “i”. In Birdwood’s account “On the Genus Boswellia” published in the Transactions of the Linnean Society of London in 1869 he describes a tree originally found by Dr. H. J. Carter, a surgeon on an East Indian survey ship. Birdwood used two “i’s” in naming the species. Many follow suit today, while the extra “i” is missing on many plant databases. I suppose in keeping the two i’s we are paying tribute to Dr. Carter and Dr. Birdwood who intently studied these beautiful trees. 3
Now what about the question of species or synonym? Birdwood first described B. carterii as a unique species. He noted thought, very distinct variations in the leaves of dried specimens supposedly from B. carterii but stated, with uncertainty, that they were simply varieties from a single species.
B. carteri and B. sacra are said to be native to only a few places in the world: southern Arabia (Omen, Yemen), northern Somalia, and Somaliland*. Dr. George Birdwood, originally designated frankincense trees in both Arabia and Somalia as B. carterii, but later considered the plants from each area as distinct species noting differences in the stamen locations of their flowers.
In 1969 English botanist, Frank Hepper distinguished the Arabian tree as B. sacra and the Somalian tree as B. carteri although no arguments for this taxonomy were mounted. 5
Likewise Théodore Monod, a French naturalist and explorer, treated the trees as separate species based on differences in their habits, although he doubted the stamen differences. B. sacra was said to branch from a non-swollen base, while B. carteri was said to have a markedly swollen trunk. 4
This habit however, at least partly, appears to be environmentally conditioned. Swelling of the trunk base is more developed in plants growing on rocks. Variations of habit appear in trees growing in different areas of Somalia. Taller trees with swollen trunks and serrate-crenate, velvety-bottomed leaves have been noted along the northern slopes of the Al Mado range, while lower, branching trees were found in the drier, stony-soiled Karkar mountains with scarcely swollen trunks and broader, undulate, less hairy leaves, and broader fruit. 4
The trees on the Arabian Peninsula typically branch from a base that is not markedly swollen, with leaflets that are undulate to sometimes serrate-crenate and fruit that varies from narrow to broad. 4
These environmentally conditioned variations lead some to conclude that only one fairly variable species, B. sacra, is distributed in Somalia and Arabia while others continue to hold the view of two distinct species.
B. carterii is recognized by the International Plant Names Index (IPNI), the Kew science Plants of the World online, and The Transactions of the Linnean Society.3, 6, 7
Woolley CL et al. offer research that concludes that B.Sacra and B.carterii are indeed two distinct Boswellia species that are not synonymous based on chemical analysis of the two.8
On the flip side The Plant List website lists both B. carteri as well as two other species and variants as synonyms of B. sacra.8
Likewise the World Checklist of Seed Plants does not accept B. carteri as a distinct species, instead it is cited as B. sacra.9
In the aromatherapy world B. carterii and B. sacra are usually treated as unique species with different aromas and very similar chemistry. B. carterii typically sourced from Somalia and Somaliland, while B. sacra is sourced from Arab countries such as Oman.
While we may not be able to clarify the mystery of species or synonym and close the case of who’s who in the world of Boswellia in the short space of this article, it seems best treat B. carterii and B. sacra as two unique species as this is currently common practice in the aromatherapy community. Since B. carterii is typically listed as the source of the hydrosol that will be the species we’ll focus on when discussing the hydrosol.
Boswellia trees like other members of the order Sapindales, are known for their fragrant resins and have been used for centuries in rituals, cosmetically, and therapeutically. The genus is named after botanist John Boswell.
Boswellia is a member of the Burseraceae family. This family is also known as “torch wood” due to the excellent light that comes from the burned wood. 10
Boswellia include trees and shrubs that are native to tropical regions of Africa and Asia, with the greatest diversity of species found in Africa and India. They are moderately sized flowering plants.
There are five main species of Boswellia that are said to produce true frankincense: B. carterii, B. sacra, B. serrate, B. papyrifera, and B. frereana.
B. carterii tis typically harvested from trees grown in in the Sanaag and Bari regions of Somalia and Somaliland*. B.sacra is native to Oman and Yemen in the Arabian Peninsula and as well as Somalia (northeastern Africa). In Oman the trees are abundant in arid woodlands, growing on steep, eroding slopes in the mountains of Dhofar.
B. serrata is native to much of India, including the Punjab region that reaches into Pakistan. B. papyrifera is native to Ethiopia, Eritrea, and Sudan and is also known as Sudanese frankincense. B. frereana is also native to northern Somalia where it is called Maydi or Dhidin or “King of Frankincense”. 10
Boswellia are dioecious, meaning they have distinct male and female reproductive structures on separate plants.
B. carterii, which is used to produce the hydrosol as well as essential oil, is a deciduous tree with one or more distinct trunks that grows from 1.5 to 8 m (4 ft. 9 in. to 26 ft. 3 in) in height. The trunks can sometimes be swollen depending on environment and are covered with tan, paper-like bark that easily peels away. This bark covers a thick, ruddy inner layer that houses copious milky resin that dries to a yellowish brown. It is unarmed – without prickles, thorns, or hooks.
The leaves are described as “crenate, undulate, and pubescent on both sides” with variations in shape, hairiness, and color. The leaves are compound with an odd number of leaflets that grow opposite of each other.
The flowers are tiny with five white or pale yellow petals and ten stamens and occur in axillary clusters. The fruit is a capsule or dry seed-containing pod, of about 1 cm (.39 in). The flowers may have four or five overlapping or imbricate petals, and an equal number of imbricate, faintly united (connate) sepals. 10
The trees tolerate inhospitable situations and often grow in ravines or rocky slopes at elevations of up to 3,900 ft (1200 m). They grow in mostly chalky or calcareous soil. The high arid regions with stony, limestone rich soil are said to be their preferred habitat. 4
Brief History, Cosmetic, and Therapeutic Use of Frankincense
Frankincense has been treasured since ancient times for both religious and therapeutic uses. It is also known as olibanum and the name frankincense is derived from Old French franc encens, which means “high quality incense”.
Frankincense trees begin producing resin at about eight to ten years of age. Resin is collected from small, shallow incisions made on the trunk or branches of the tree. The quality of resin depends on the habitat and time at which the resin is collected and is graded based on color, purity, aroma, age, and shape.
“Al-Hojai” is harvested during the hottest season, “Annajdi” following the monsoon months, Ashazri” from the first cuts of the season, and “Asha’bi” or “Assahili” harvested during the coldest part of the year. “Al-Hojari” or “Hojari” is considered the finest collected from trees that grow in the dry, arid elevated regions not exposed to fog or monsoons, and “Asha’bi” the least precious because trees are close to the ocean and affected by monsoonal rains. 10, 11
Archaeological evidence cites the trading and numerous uses of frankincense/incense by ancient civilizations. Ancient Jews, Greeks, Romans, Egyptians, Mesopotamians, Christians, and Muslims used frankincense in religious, social, and cultural events and rituals. 10
Early cosmetic uses of frankincense included the production of perfumed oils made with resin and other plant oils and spices. The perfumed oils were popular in the public baths of the Roman Empire. Perfumed oils extracted from frankincense were used into modern times by perfumers. 10
The black soot of burned incense produced kohl, a black eyeliner used by ancient Egyptian men and women. Additional beauty unguents used frankincense and other fragrant resins for the skin and hair. Modern day soaps, creams, and skin care regimens feature frankincense resin or distillate. 10
Frankincense was also prized for medicinal use. Ebers Papyrus sites the use of frankincense for throat infections, phlegm reduction, easing nausea and vomiting, soothing asthmatic attacks, and staunching bleeding.
In ancient Chinese culture it was used to improve blood circulation, soothe indigestions, and for wounds and injuries due to its anti-microbial and skin supportive properties. 10
Ayurvedic medicine used frankincense gum to ease arthritic and inflammatory conditions as well as in pulmonary disease and gastrointestinal conditions. 10
Additionally frankincense has been used for ulcers, dysentery, fevers, vomiting, tumors, coughs, dental problems, and wounds.
Currently frankincense is highly prized to nourish and rejuvenate the skin as well as ease tension, soothe muscle and head aches, support respiratory health, and to support meditation. 10
Frankincense is also touted as greatly beneficial against cancer and tumors. However, frankincense extract that includes hydrophilic (water loving compounds) or the resin appears to be the most effective rather than the essential oil or hydrosol with the majority of studies being done in vitro. 12
The Benefits of B. Carterii Hydrosol
B. carterii hydrosol aroma is said to be sweet, unmistakably frankincense, slightly resinous, and warmer than steam distilled oil. Catty describes it as extraordinary and the taste as bitter but not unappealing. When diluted it’s said to become soft, warm, and dry. 13
Aromatherapist Amy Kredydin describes the hydrosol as woody, terpenic, and resinous with a woody, medicinal, balsamic flavor. 14
I find frankincense hydrosol lovely, earthy, with a characteristic yet light frankincense aroma. In my experience many people adore the aroma of frankincense and the hydrosol and others find it overpowering and unappealing.
B. carterii hydrosol, like the essential oil and resin has numerous benefits. The hydrosol is estimated to have a shelf life of 18 months with a pH of 4.7 to 4.9. 13
The hydrosol is said to be useful for meditation, rituals, and energy work and Catty describes applications as “experimental”. Like the essential oil the hydrosol seems to support respiratory health – useful to dry excess mucus in the lungs and expectorate phlegm. 13
Internally frankincense is said to be drying and diuretic. Catty suggests exploring the hydrosol in conditions where pus or discharge are present as well as for infections of the reproductive and urinary systems in combination with Cistus or sandalwood. It may also be beneficial as a gargle for mouth or gum infections. 13
Kredydin advocates using the hydrosol for meditative and spiritual practices, to energetically clear a room, and for skin formulations. She cites that one client spritzed the hydrosol on her hands daily for several months and noted the pigmented spots on her hands noticeably faded. 14
Like the essential oil, the hydrosol is well touted as wonderful for the skin. It can simply be misted on the face and left to dry to improve the texture of the skin or in face masks for lifting and improving the appearance of the skin.
Personally I love using frankincense hydrosol in recipes for skin and hair (use in the water portion of hair and skin formulations) as well as oral rinses such as natural mouth wash along with peppermint, cinnamon, or myrrh hydrosols. Frankincense hydrosol has no known safety concerns.
Conservation Status of Frankincense Species
As with all essential oils and hydrosols it is vital to purchase from suppliers who source them sustainably. B. sacra is listed as near threatened on the International Union for Conservation website. 15 Likewise on conscientious distillers websites they state that B. carterii is on their sustainability radar and they work with distillers who take proper steps to safeguard sustainable harvesting practices and ethical work practices. 16
Frances Bongers et. al reveal evidence that a collapse of the B. papyrifera is occurring due to over-exploitation and ecosystem degradation as well as other issues. The authors state the situation is similar for other Boswellia species and call for active protection and restoration of the remaining Boswellia woodlands to ensure its availability for future generations and to allow for ethical income for regions that produce frankincense. 17
While the demand for frankincense grows it is vital that we choose vendors who work with distillers that source the resins in a sustainable manner.
If you wish to use a hydrosol other than frankincense consult a certified aromatherapist or knowledgeable aromatherapy practitioner. I’ve mentioned a few alternatives below.
Alternatives to frankincense:
Respiratory support: Eucalytus, or Hyssopus officinalis (hyssop) hydrosols.
Skin support: Daucus carota** (Carrot seed), Rosa x damacena (rose), and Pelargonium spp. (rose geranium) hydrosols.
Anti-inflammatory support: Symphytum officinalis** (comfrey), Rosmarinus officinalis** (rosemary), and Achillea millefolim (yarrow) hydrosols
** (avoid Daucus carota during pregnancy, do not use Symphytum officinalis internally except under professional supervision, avoid Rosmarinus officinalis during the first trimester of pregnancy and with high blood pressure. All other hydrosols have no safety concerns.)
Frankincense is a beautiful, highly prized gift from nature with many therapeutic benefits. Once reserved for deity, kings, and priests, this precious resin continues to command respect. As with all treasures from the earth we must use it wisely and with care so that its use is available for many generations to come.
Gorgeous Skin Toner
Frankincense is gorgeous for the skin and works amazing as toner in part of a skin care regimen. Cleanse the skin, spritz with the toner, and moisturize to support healthy skin.
You will need a clean 2-oz. to 4-oz. glass spray bottle.
· 30 mL frankincense hydrosol (Boswellia carterii)
· 30 mL rose hydrosol (Rosa x damacena)
· 3 - 8 drops lavender essential oil (Lavandula angustifolia) optional
· 1 drop rose essential oil (Rosa x damacena) optional
· 1 drop carrot seed essential oil (Daucus carota) optional
· 20 – 40 drops Solubol dispersant optional
Instructions for Making and Use:
Add essential oils to the glass bottle and solubol if using. Mix gently to combine. Add hydrosols, cap the bottle, and mix gently to combine. To use: after cleansing the skin, mist over the face, avoiding eyes, and let dry. Follow with moisturizer if desired. Or simply mist on face morning and evening or as desired to support skin health. Make a fresh batch every few weeks.
Cautions: Avoid using in pregnancy.
Frankincense Clay Mask
Try this mask to soothe and support dry fall or winter skin. Frankincese, rose, and rose geranium all offer wonderful benefits for the skin. Avocado oil is nourishing and moisturizing and honey acts as a humectant to draw moisture into the skin.
Ingredients and Equipment:
Stainless steel or glass bowl for mixing
Spoon for mixing
1 tsp. of Rhassoul or Benonite clay
1 tsp. avocado (Perea gratissima) oil
1 tsp. honey
Essential Oils and Hydrosols:
1 drop geranium (Pelargonium graveolens) or lavender (Lavendula angustafolia) essential oil
1 or more tsp. frankincense (Boswellia carterii) hydrosol
Directions for Making and Applying the Mask:
1. Clean equipment with 70% isopropyl alcohol and/or warm water and dish soap.
2. Add all ingredients to the bowl and mix well to form a smooth paste.
3. Spread mask on face and neck.
4. Relax and enjoy for 10 to 20 minutes.
5. Rinse mask with warm water and pat face dry.
6. Enjoy your beautiful skin.
* Somaliland at present is a self-declared state formerly part of northern Somalia that engages in diplomatic operations with the United Nations and other groups but is not officially recognized as a state by foreign governments.
Aromatic blessings my friends,
1.Bible Gateway Website, Book of Matthew 2:10-12, accessed October 15, 2019: https://www.biblegateway.com/passage/?search=Matthew+2:10-12&version=NIV
2. Middle East Institute Website, The Story of Frankincense, accessed October 15, 2019: https://www.mei.edu/sqcc/frankincense
3. The Transactions of the Linnean Society of London Volume XXVII (1869) Accessed October 15, 2019: https://www.biodiversitylibrary.org/item/87717#page/146/mode/1up
4. M. Thulin and A.M. Warfa, (1987), The Frankincense Trees (Boswellia spp., Burseraceae) of Northern Somalia and Southern Arabia, Kew Bulliten, Vol 42. No. 3, pp. 487-500, accessed from: https://www.jstor.org/stable/4110063?seq=1#metadata_info_tab_contents
5. F. N. Hepper, (1969). Arabian and African Frankincense Trees. The Journal of Egyptian Archaeology, 55(1), 66–72. https://doi.org/10.1177/030751336905500108
6. International Plant Names Index (INPI) website, Boswellia carteri, accessed on October 6, 2019 from: https://www.ipni.org/n/127038-1
7. Kew Royal Botanic Gardens Science: Plants of the World Online, Bowswelia carteri accessed on October 6, 2019: http://powo.science.kew.org/taxon/127038-1
8. Woolley, CL et al. (2012) Chemical differentiation of Boswellia sacra and Boswellia carterii essential oils by gas chromatography and chiral gas chromatography-mass spectrometry, J. Chromatogr, Oct. 26 1261:158-63 accessed on October 6, 19 from: https://www.ncbi.nlm.nih.gov/pubmed/22835693
9. Govaerts, R. (1996). World Checklist of Seed Plants 2(1, 2): 1-492. MIM, Deurne. [Cited as Boswellia sacra.]
10. A. Al-Harrasi, A. L. Khan, and S. Asaf (2019). Biology of the Genus Boswellia, Switzerland, Springer Press
11. Wayback Medicine Website, Omani Sites on the World Heritage List Webpage, accessed on October 6, 2019 from: http://omanwhs.gov.om/English/Frank/FrankincenseTree.asp