Ironwood tree

The ironwood tree is considered native to the Sonora Desert as it is found only the states of Sonora, Baja California Norte and Baja California Sur in Mexico and Arizona and California in the United States.[1] Olneya tesota is the slowest growing and the tallest in the Sonora Desert, with specimens able to reach heights of up to fifteen feet, if near relatively stable sources of water. It accounts for a fifth of the Desert’s biomass mostly due to the density of its wood. The shade provided by these trees is essential for a number of other desert plants and animals.[2]
The species is protected by the Mexican government because of its overexploitation and deterioration of habitat.[1] The plant is not considered to be in danger of extinction as its range is over millions of hectares and with thousands of trees, however its slow growth and use in handcrafts and firewood puts it in some danger. In 1992, before it received protection from the Mexican government in the 1990s, 21,000 tons of the wood was converted into charcoal. Ninety percent of this charcoal was exported from Sonora to the United States.[1][2] Today, carving is not the biggest danger to the tree but rather the conversion of desert into pasture and cropland.[1][2] Other efforts to conserve the tree include the establishment of organizations such as Pro Palo Fierro, to develop ways to use the resource in a sustainable manner. Since the plant is found in two countries, efforts involving the US have included organizations such as Conservation International and the Desert Botanical Garden in Phoenix.[2]