The Mexican White Pine

The Arnold Arboretum has more than 40 species of pine growing on its grounds from throughout the geographic range of the genus. The Mexican White Pine, Pinus ayacahuite, is particularly intriguing because it is the Arboretum’s southernmost representative of the genus as well as being one of the very few Mexican plants hardy here. The 24-year-old specimen, propagated from seed from the Royal Botanic Garden, Kew, England, is located in the conifer collection in Kent Field. Not only does it demonstrate the remarkable quality of being hardy in the Boston area, but it exhibits outstanding ornamental features as well. Branched to the ground, it is densely pyramidal, with slightly ascending branches in relatively regular whorls. The needles, arranged in groups of five, are about five inches long, glaucous-green and pendent. The tree has been compared to the Himalayan Pine, P. grifrathii, because of its drooping foliage, but exhibits