Frankincense, also known as olibanum, is an aromatic resin derived from certain trees. It has been used for thousands of years in incense, perfumes, and traditional practices across various cultures. This resin is prized for its complex and distinctive scent, often described as woody, earthy, with nuanced sweet and citrusy notes.
The Boswellia Tree
Frankincense originates from trees belonging to the Boswellia genus, part of the Burseraceae plant family. These moderate-sized trees or shrubs thrive in harsh, arid environments. A distinguishing feature of many Boswellia species is their peeling, papery bark. Different species within this genus produce distinct types of frankincense resin, each with unique characteristics. Trees begin yielding resin when they are approximately eight to ten years old, with some remaining productive for up to forty years.
The resin produced by Boswellia trees serves as a natural defense mechanism. When the tree’s bark is injured, the sticky sap oozes out, acting like a protective bandage. This process helps the tree seal wounds and guard against disease or insect infestations. The chemical composition of the resin varies significantly between species, influencing its aroma and properties.
Primary Geographical Origins
The Boswellia trees that yield frankincense are found in arid regions across the Arabian Peninsula, Northeast Africa, and India. Oman and Yemen are sources for Boswellia sacra, with the Dhofar region in southern Oman known for its high-quality resin. In Northeast Africa, Somalia produces frankincense, home to Boswellia frereana and Boswellia sacra. Ethiopia, Eritrea, and Sudan are sources for Boswellia papyrifera.
These trees grow in challenging environments, including rocky slopes, ravines, and mountainous terrain, often at elevations up to 1,200 meters. Climate, soil conditions, and even coastal fogs can influence the growth of the trees and the quality of the resin produced. For example, trees in fog-laden zones of Oman are known to yield high-quality resin. In India, Boswellia serrata is prevalent in dry mountainous areas, including Rajasthan and the Western Himalayas.
From Tree to Resin
The collection of frankincense resin involves a method known as “tapping” or “stripping.” Harvesters make shallow incisions into the outer bark of the Boswellia tree. This intentional cut prompts a milky, sticky liquid to exude from the tree.
Once exposed to air, this sap begins to harden and crystallize, forming “tears” of frankincense. This process takes about one to four weeks. Harvesters then return to scrape off these hardened resin tears from the tree. The initial scraping yields a lower quality resin that may contain more impurities, with subsequent collections from the same incision producing clearer, higher-grade material. After collection, the resin tears are transported and further dried, sorted by quality.
Distinguishing Frankincense Varieties
Frankincense is not a single, uniform product but encompasses various types, each with distinct characteristics influenced by the Boswellia species and its geographical origin. One variety is derived from Boswellia sacra, found in Oman and Somalia, which produces resin tears ranging from greenish to white or silver. The “Royal Green Hojari” from Oman is valued for its sweet, clean, and slightly citrusy aroma.
Boswellia frereana, from Somalia, is referred to as Maydi or “the king of all frankincense” in its native region. This resin forms large, golden-colored tears and is known for a softer, sweeter aroma with balsamic and lemon undertones. Boswellia serrata, or Indian frankincense, yields smaller tears and is a staple in Ayurvedic practices. Boswellia papyrifera from Ethiopia, Eritrea, and Sudan produces a more transparent, oily resin characterized by fruity and orange overtones. These variations in color, shape, and aromatic profile contribute to the diverse applications and market for frankincense.