El Arbol del Tule: The Ancient Giant of Oaxaca Zsolt Debreczy and Istvan Racz The famous tree that has puzzled travelers and botanists for hundreds of years with its legends now raises new questions about its future. Outside the city of Oaxaca, on the ancient lands (5,100 feet), form a wide valley up in the Sierras. of the Mixtecs and Zapotecs in southern The area has only two distinct seasons: a humid, Mexico, stands a tree, perhaps the most famous often cloudy, hot, rainy season typical of the and most frequently measured among the "summer-rain tropics" south of the Tropic of giants: a unique specimen of the fast-growing Cancer, and a warm, dry "winter" season with southern bald cypress, Taxodium mucronatum, bright sunny days, cool nights, and frequent known by the Aztecs as an ahuehuete, the frosts in the mountains. Near the city, frost has "graybeard of the swamp." What "General been reported only once a decade or so. Grant" is to the giant sequoias, El Arbol del At one time, the tree ruled over wide fields of Tule is to the bald cypresses. the brown-headed cattail-Typha domingensis, The Mexican bald cypress is a member of the a close ally of T. latifolia of the north temperate Taxodiaceae, the family of giant sequoias, Cali- regions of the world-called the tule in the fornia redwoods, and bald cypresses, which, native Zapotec tongue. Today, instead of an excluding tropical species, has the greatest extensive swamp supplied by such rivers as the potential of all tree families for achieving both Atoyac and its tributary, the (local) Rio Grande, great age and enormous size. Amazingly, this flowing down from the nearby Sierra de Juarez, family of giants, like other conifers, is described the tree is surrounded by a neatly maintained as primitive because of its elementary conduct- lawn, colorful flowerbeds, and a wrought iron ing system of single-celled tracheids. In fact, fence. The growing village of Tule has swal- this simple system can carry water and miner- lowed the swamp, its buildings and yards als to heights over 110 meters (366 feet), even gradually encircling it, forming a lethal noose under extreme conditions such as those found around it. on the slopes of the Sierra Nevadas of western Our First Encounter North America, which remain dry for many months at a time, and those in the waterlogged, Having seen giant sequoias and redwoods in oxygen-deficient swamps, the habitat of Glyp- both the higher Sierras and the Coast Ranges of tostrobus of southeast China and Taxodium of California, we were accustomed to the drama of the southeastern United States and Mexico. large specimens. However, when engulfed by Taxodium mucronatum represents the south- the spreading arms of Arbol del Tule, we experi- ernmost species of the genus, which was once enced a totally different degree of awe, not found all over the Northern Hemisphere but is comparable to anything we had previously now restricted to North America. encountered. While the big trees of California The giant tree grows in the town of El Tule, are majestic, like the skyscrapers of downtown little more than fifteen kilometers from the city New York they are out of reach. Arbol del Tule of Oaxaca, the capital of the southern Mexican is an accessible "seated giant," welcoming us state of the same name. The highlands where it with broad, sweeping branches that extend is located, at an elevation of about 1,550 meters almost the length of two tennis courts. El Arbol del Tule, near Oaxaca City, Mexico. 4 Although the tree is not particularly tall, it takes seventeen people with outstretched arms to encircle its gigantic trunk. Fascinated at first by its enormous dimensions, we soon turned to the details of the tree. Each limb, tower- ing upward, could itself be an inde- pendent tree of huge size. Like a gothic cathedral, arches rise above arches as the limbs disappear into the jungle of the crown 40 meters (130 feet) above, simultaneously reaching outward an incredible dis- tance. Dramatically fluted in out- line, the trunk has an air of mystery: sunlit ribs alternate with deeply shadowed recesses that are partly curtained by a veil of fine, light- green foliage. -: The Inevitable Question ~ A correlation between the age and size of trees, at least within a species, would seem logical: the big- ger the tree, typically the older it is. Seeing the almost 60-meter (200- foot) circumference of our giant, one assumes that this tree must be thou- sands of years old. Poets, politicians, scientists, and the technically inge- nious have tried to answer the inevi- table question: how old is it? Estimates have varied; some have gone as high as three thousand years, as suggested by A. Villasenor in 1892, or even six thousand, as put forward The giant tree dwarfs schoolboys and the chapel of Santa Maria ahke m these postcards. The sign tells us that m 19877 El Arbol del Tule was 41.85 meters (1377 feet) high, 579 meters (190 feet) m cmcumference, and 14.5 meters (48 feet) m diameter, with an estimated volume of 816,829 cubic meters and a weight of 636,107 tons. In 1992, our clmometer measurement showed that the tree was only 39.40 meters (130 feet) high, which, assuming the data are correct, indicates an almost two-meter (seven- foot) decrease m height m five years. 5 Taxodium mucronatum differs httle from its northern relative, T distichum. C. S. Sargent m his Silva of North America (1896) wrote that "it may prove to be a mere geographical form of our tree " Others, hke Harper m 1902, consider it a "Sonorized" form of the northern species. Except for its "knees," which are absent or short and roundish, the differences he mostly m phenological characters: the growth of the southern tree is more compact; its cones are smaller and leaves shorter, often prumose gray ("bloomy") and semipersistent. These two old trees grow m the highlands near Oaxaca. 6z by E. W. Berry in 1923. An old legend among the tree, another question has been raised through local Zapotecs and Mixtecs tells us that the tree, the past two centuries: is it a single tree or a along with several others nearby, was planted group of trees that have coalesced to form a for the benefit of the people by Pecocha, a repre- single individual? Although the tree is thought sentative of the Aztec god of wind and storms, to have been visited by Alexander Humboldt on Ehecatl. This story puts the age of the tree at his visit to Mexico m 1803, evidence suggests around fourteen hundred years. that he never reached Oaxaca and therefore Estimates, to be correct, should consider the never visited the tree. However, he wrote in his tree’s rate of growth, but in the case of the Tule Political Essay on the Kingdom of New Spain: In the village of Santa Maria del Tule, three leagues from the capital, there is an enormous sabmo (Cupressus disticha [now Taxodium mucronatum]), the trunk of which is 36 meters [120 feet] in circumference. This old tree is even more corpulent than the cypress of Atlixco of which we have spoken above, than the Dragon tree of the Canary Isles and than any of the baobabs (AdansomaJ of Afmca. But - exammed closely, senor Anza has observed that, that sabmo ’~ , which is such a surprise to travelers is not a smgle mdt- vidual but a group of three trunks united ~II: 45-47). In 1892, Alejandra Villasenor summed up nearly a century of controversy: The trunk of the tree of Santa Maria del Tule, far from bemg compact and almost cylindri- cal, is, on the contrary, rough- barked, unequal, and fissured, covered with senile excres- cences [burls], some of large size, with bold projections which made a certam Sr. Anza Some characteristics of Taxodmm mucronatum are strongly mfluenced that it was not a by climate. The compound leaves are semipersistent the fohage of the suppose premous year detaches only when the new leaves unfold The southern smgle tree but three united; species is less cold-hardy than its northern cousm, especially m sudden but later observations by Dr. J. frosts. When cultivated m areas where the winter temperatures fall Bolanos in 1840 and by other below freezmg, most of the green fohage becomes yellowish brown and people have shown the error falls, even on the trees of Tule. of the supposition. In the Umted States, the Montezuma bald well cypress grows Botanist Bolanos throughout the West and mostly below 30 degrees North latitude in the Juan climbed the tree to the East while it is easy to cultivate m the Mediterranean basm up to 40 to point 44 degrees North, and m western Europe, it survives far above the where the common trunk ends latitude of 50 degrees North. and the primary branches begin ? 7 Ahuehuete gallery forest near Sola de Vega, Oaxaca Note the root system weavmg a protectme lattice on the mverbank. Instead of adaptation to anaerobic swamps, Taxodium mucronatum is adapted to pemodically high mverbeds and mversides. The fantastic root systems grasp the nversides, fencmg the mverbed with such ef ficiency they seem to be created for that purpose. At Sola de Vega, the most beautiful nverbed habitat of the species is still untouched, promdmg dramatic mews of trees 12 to IS meters (40 to 50 feet) tall. 8 and found a large enclosed place "which could serve as a habitation in case of need." This obser- vation convinced him that the trunk belonged to one individual and that the divisions at the base of the trunk, considered to stem from separate trees, are only parts of a sole specimen.