Common Name(s): Little Leaf Bursera, Torote, Torote Colorado

Synonym(s):

Family: Burseraceae

Native To: Arizona and California in the United States, and Sonora and Baja California in Mexico.

Native Habitat: From low elevation mountain ranges to gravelly/rocky slopes and open flats, wherever the sun is hot.

Growth Habit: Small multi-stemmed tree growing to 25 feet tall with an excessively thick trunk that can reach 3 feet in diameter.

Flowering: Early summer

Distinguishing Characteristics: The red-tipped branches usually spread wide and have a twisted appearance. The Leaves, which are 2 to 3 inches long, are alternate, pinnately compound with 7-35 pairs of tiny leaflets. The small, cream colored flowers are dioecious, and hang in panicles. The fruit is is a berry about the size of a lentil, with several seeds. The oversized, water-filled trunk and older branches are covered with a bark that is papery, with the outer layer exfoliating in thin tissues, exposing a bright rust or golden layer. As the tree expands in girth, there might be several layers of this bark visible.

Natural History and Cultivation Notes: The UA Torotes are not really suited for Tucson’s weather, since they suffer cold damage even above freezing. Luckily, they are in a perfect spot. They are thriving in a hot and bright microclimate on a south facing wall, midway up some stairs on the north entrance to the Integrated learning Center. In this location they are above the cold air drainage and in full sun all year. We thank Mickey Reed, a local grower of succulents and "weird plants" for supplying these trees in 2002. A third tree is getting established in the Krutch Garden.

In western Sonora this tree is common and conspicuous, and in some areas of Baja California it is the dominant tree.

Ethnobotany: According to Felger’s Trees of Sonora, the Seri and Coahuilla people used these trees for many medicinal purposes such as treatment of headache, cuts and scratches, lice, skin diseases, sores, stingray wounds, and venereal disease. Other references mention tea from the twigs, and caulking from the sap, amongst other uses.

Nonetheless, it’s the aromatic resin or sap from these trees that is so important, and has been studied so extensively. The genus is prevalent in many tropical dry forests in southern Mexico, and the Aztec and Mayan cultures are known to have used the sap from several Bursera species. The sap which easily "bleeds" from the cortex and bark of the plant when wounded, contains strongly fragrant oils and is known in the Mayan and Aztec cultures as copal. Copal, which is technically not specific to any particular species of Bursera, has been documented as an important part of pre-Columbian ceremonies. In religious and secular events, the resin or gum is burned as incense. Copal is mentioned in the Popol Vuh, the great Mayan sacred book transcribed into Latin in the 1500s.

Even today, copal is used in traditional Mayan and Mixtec cultures. The resin is burned in special burners to emit its thick smoke, the fumes of which are said to cure various illnesses. Harvesting the resin involves notching the trees to induce the sap to flow. As the resin is boiled in water, it rises to a froth on top of the mixture and is skimmed off. The gum is then cooled and shaped into brittle lozenges by hand. Three commercial incense copals are on the market today in Central America. (Most of this information is from Case et al. 2003. Chemistry and Ethnobotany of Commercial Incense Copals, Copal Blanco, Copal Oro, and Copal Negro, of North America. Economic Botany.)

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