DEPARTMENT OF BOTANY
International Boundary Commission
International Boundary Commission
(1891 - 1896)
In the 1870s and 1880s, border disputes broke out when valuable natural resources were discovered near the United States-Mexican border. The International Boundary Commission, which set out in 1891, consisted of two main parties, one from the U.S. and one from Mexico. Although the replacement of mid-19th century monuments marking the border between the two countries was the main goal of the expedition, Edgar A. Mearns, the assistant surgeon on the U.S. field party and an experienced amateur naturalist, recognized the potential for a valuable natural history survey. As Mearns wrote to Lieutenant Colonel J. W. Barlow, the leader of the American expedition, “such an opportunity of studying and gathering specimens from this extensive, unexplored, and inhospitable region will not soon occur again.”
The resulting botanical collection, which Frederick V. Coville called “an excellent representation of the vegetation from El Paso to San Diego,” contained about 10,000 collection numbers which are now deposited in the United States National Herbarium. Specimens of Quercus rugosa (netleaf oak) were collected “with ripe fruitage” above 6,200 feet on the summit of the San Luis Mountains in Arizona. Also deposited in the Smithsonian collection is a specimen of Zephyranthes longifolia (copper zephyrlily), a plant that “grows abundantly around rock croppings on the western edge of [Animas] Valley” in New Mexico.
When Mearns passed through desert lands west of El Paso, he noted the botanical features of the habitat which he described as “though dry, it is not infertile.” Prosopis juliflora (mesquite), Yucca, and various Artemisia (sagebrush) species were very common, and sometimes grew unusually large. The western half of the desert was “largely covered with black grama grass [Bouteloua eriopoda]”, in addition to Sarcobatus (greasewood) and several other plants. Cacti were few in number, but many different species were found.
Mearns encountered several plants with practical uses, such as Chamaesyce prostrata (rattlesnake-weed or prostrate sandmat), a plant “much used by Mexicans [and] Indians” to treat rattlesnake bites. Also, the cactus Ferocactus wislizeni (candy barrelcactus) was “a very good source of ‘cactus candy’ [which is made] from this cactus, with the addition of sugar.”
Budgetary shortfalls led Congress to deny funding to complete the biological report of the survey, so it was never published. However, the report would have been about 400 pages long, including information on “timber, forage, local medicinal plants, dyes, tans, native foods, and other important subjects,” in addition to 50-100 illustrations of new species. This was the first biological survey made “with the definite object of defining the geographic range of the individual species of animals and plants, thus defining the limits of the natural life areas,” so the published results would have been a valuable addition to American botany.
Assistant Secretary in charge of the United States National Museum, Correspondence and Memoranda, 1860-1908. Reference Unit 189, Box 81. Smithsonian Institution Archives.
Edgar Alexander Mearns Papers, circa 1871-1916, 1934, and undated. Reference Unit 7083, Box 4. Smithsonian Institution Archives.
Frederick Vernon Coville Papers, 1888-1936 and undated. Reference Unit 7272, Box 3. Smithsonian Institution Archives.
Report of the Boundary Commission upon the Survey and Re-marking of the Boundary Between the United States and Mexico West of the Rio Grande. 1891-1896. Washington: Government Printing Office, 1898.
Richmond, Charles W. “In Memoriam: Edgar Alexander Mearns.” The Auk: A Quarterly Journal of Ornithology, 35, no. 1 (1918): 1-18. https://academic.oup.com/auk/article-abstract/35/1/1/5265752?redirectedFrom=fulltext (July 19, 2010).
USDA PLANTS database. United States Department of Agriculture, Natural Resources Conservation Service. National Plant Data Center. http://plants.usda.gov/ (for information on plant species Quercus rugosa, Zephyranthes longifolia, Prosopsis juliflora, Bouteloua eriopoda, Chamaesyce prostrata, and Ferocactus wislizeni, and the genus Sarcobatus; accessed July 19, 2010).