By José Delgadillo Rodríguez, PhD

The Boojum tree is surely the most representative plant found in the central arid desert of the peninsula of Baja California. It is specially, the most representative one in the area called Valle de los Cirios in the Vizcaino Desert which is also known as Cochimí Desert (Delgadillo, 1998). The Boojum tree (Fouquieria columnaris) belongs to the botanical family Fouquieriaceae. It has a single genus Fouquieria and 11 different species, including the ocotillo. Its columnar form has attracted the attention of many botanists. This fleshy stem plant is considered as a unique specimen among Mexican flora and, of course, among a select group of species in the world with such features.

An identical biotype (biological form) can be found in Karoo, Africa, an oceanic desert similar to the Vizcaino Desert. We are talking about the Pachypodium namaquamum, a plant that also has a fleshy stem. Because of this fact, we can deduce that these biotypes reflect an ancient adaptation to a type of climate that did not suffered significant oscillations.

In 1751, Father Fernando Consag published a text that proves the existence of the Boojum trees and their properties. For these were tall, straight and branchless trees, Father Consag and his entourage gave them the name of cirios which in Spanish means candle. On the other hand, Cochimí indians called them milapa (Leon-Portilla, 1988). In the United States, it is known as Boojum tree that refers to “a mythical thing that inhabits desolate and remote places” (Humphrey, 1974).

These plants are like giants, they can measure up to 65 feet, but the tallest one known was 86 feet tall. Moreover, some people compare them to carrots because of their shape. However, it is very common to find plants with branches and capricious formations.

The Boojum tree blooms in August and September. Its flowers are small with creamy-yellow corollas. They have a strong fragrance that smell like honey, and they produce a sweet nectar. Some reports indicate that 15 different species of bees visit these flowers (Humphrey and Werner 1969, in Henrickson, 1972).

The terminal growth of their stems apparently occurs only during the winter-spring period. This never happens during the summer or any other season. During years of unusual winter rains their growth is considerable in contrast with little or no growth during years of extreme drought (Humphrey, 1974). This slow-growing species is found on rocky hillsides and floodplains, mainly in deep soils of granitic-clay origin that facilitate good drainage processes. They are also found in other types of soil such as those of volcanic origin, and humidity produced by fog plays a very important role as their main source of water.

The Boojum tree is a plant with a restricted (and thus endemic) distribution in the peninsula of Baja California, a small portion of Puerto Libertad (Sierra Blanca) in Sonora and Ángel de la Guarda Island. However, the greatest density area is right in the middle of the peninsula, from the south part of El Rosario, Baja California to the northern slopes of the Tres Vírgenes volcano, in Baja California Sur. This arid region has an average of 73 to 140 mm of annual rainfall, mainly from January to April and less rainfall between August and September. Miguel del Barco (León-Portilla, 1988) referred to this plant as “a type of fleshy vegetable, a tree that is not found in another part of America or elsewhere in the world, not even in California.”

The Boojum tree is part of a type of vegetation called sarcocaulescente (Succulent stems), and it is associated with the following species of plants: Baja elephant tree (pachycormus discolor), Mexican giant cardon (Pachycereus pringlei), ocotillo (Fouquieria splendens), Adam´s tree (Fouquieria diguetii), datilillo (Yucca valida), creosote bush (Larrea tridentata) and a wide variety of cactuses and agaves. In addition, this species is associated with an epiphytic plant called ball moss (Tillandsia recurvata) and hanging lichens such as the Ramalina menziesii (Lace Lichen), mainly in areas near the Pacific coast populations that present high humidity.

In this regard, Humphrey (1974) mentions that the key factor that affects populations near the Pacific coast and their establishment are the constant winds that cause soil desiccation. Although the fog contains substantial humidity, it rarely occurs for it to stay for longer than 24 hours to keep the soil moist and prevent drought. Consequently, the hillsides that are well oriented and protected from the wind are where Boojum trees are abundant.

The exploitation of this important resource has been limited to the use of its thin wood to build small houses and decorate walls, and it has become highly demanded for this reason. What is concerning about this is that the law allows the commercialization of dry fallen trees, so people illegally induce their death by using barbed wire to strangle and cut the tree from its base.

This species is endemic to Mexico, yet it is not protected by Mexican norms (NOM-059-SEMARNAT-2010). This means that it is necessary to make sufficient scientific studies that justify their inclusion on the list of protected species. However, it is included in Appendix II of the Convention on International Trade of Endangered Species of Flora and Fauna (CITES for its acronym in English) that Mexico has already signed. This appendix includes species that are not necessarily threatened but may become so unless specimen’s trade is subjected to strict regulation.

The Boojum tree was considered as a priority species for conservation in Mexico by the Secretary of Environment and Natural Resources (Semarnat in Spanish) with the purpose of developing the national program for its conservation. Moreover, the Boojum tree gave its name to the decree of 1980 that established the Special Protection Area of ​​Flora and Fauna known as Valle de los Cirios.

About the author

Dr. José Delgadillo Rodríguez is Professor of Botany and responsible of the BCMEX Herbarium at the Faculty of Sciences of the Autonomous University of Baja California (UABC for its acronym in Spanish) in Ensenada. Email: jdelga@uabc.edu.mx

References

• Delgadillo, J. 1998. Florística y ecología del Norte de Baja California. 2da. Universidad Autónoma de Baja California, Mexicali, B.C. 405 pp.
• León-Portilla, M. 1988. Miguel del Barco: Historia Natural y crónica de la Antigua California [adiciones y correcciones a la noticia de Miguel Venegas]. Instituto de Investigaciones Históricas, Universidad Nacional Autónoma de México, D.F. 482 pp.
• Humphrey, R.R. 1974. The Boojum and its home: Idria columnaris K. and its ecological niche. The University of Arizona Press, Tucson. 214 pp.
• Henrickson, J. 1972. A taxonomic revision of the Fouquieriaceae. Aliso 7(4): 439-537.
• SEMARNAP, 1997. Programa de conservación de la vida silvestre y diversificación productiva en el sector rural 1997-2000. Secretaría de Medio Ambiente, Recursos Naturales y Pesca (Semarnap). México, D.F. p. 133.
• Wiggins, L.I. 1980. Flora of Baja California. Stanford Universty Press. Stanford, California. USA. 1025 pp.