Earth is home to a vast array of trees, with around 73,000 recognized species and countless more awaiting discovery. This excerpt from “Remarkable Trees” delves into three truly astounding species, showcasing the remarkable diversity and captivating stories woven into the world’s arboreal tapestry.
The Manchineel: A Tree of Death
The manchineel (Hippomane mancinella), a member of the spurge family, holds the unfortunate title of the world’s most dangerous tree. Its milky sap, exuding from any wound on its trunk or branches, is highly caustic. Contact with skin can lead to blistering burns, while exposure to the eyes can cause temporary blindness. Even standing beneath the tree during rain poses a risk, as contaminated raindrops can inflict the same effects. Native to the tropical regions of southern North America, the Caribbean, Central America, and northern South America, the manchineel grows to impressive heights, reaching up to 50 feet tall. Its roots play a crucial role in preventing coastal erosion. While its fruits, resembling small green apples, may appear inviting, they are intensely toxic. The fruit’s flesh, if ingested, causes severe burning and ulceration of the mouth and throat, resulting in excruciating pain. Every part of the manchineel is toxic, leading locals to mark the trunks with a red X or warning signs. Despite its dangers, the wood is cautiously used in furniture making, but even burning it can cause serious eye problems due to toxic smoke.
The manchineel’s notoriety extends beyond its physical properties, appearing in literature and opera. The 18th-century naturalist Mark Catesby documented his agonizing experience after the tree’s juice entered his eyes, leading to temporary blindness. References to the manchineel can be found in works such as “Madame Bovary” and “The Swiss Family Robinson.” Its sinister reputation even graces operas, including Giacomo Meyerbeer’s “L’Africaine,” where it serves as the heroine Sélika’s chosen method of suicide.
The Wollemi Pine: A Living Fossil
In 1994, David Noble, a bushwalker in Australia’s Wollemi National Park, stumbled upon an unfamiliar and unusual tree. This discovery would send shockwaves through the plant world, revealing a new species unknown to science. The tree was named Wollemia nobilis, the Wollemi pine, honoring both the location and its discoverer. The Wollemi pine, despite its name, is not a true pine but a member of the ancient Araucariaceae family, once abundant during the Jurassic and Cretaceous periods. The closest relatives of the Wollemi pine, the kauri and monkey puzzle, are mostly found in the Southern Hemisphere. Fossil records revealed that the Wollemi pine had been presumed extinct for two million years, making its rediscovery a remarkable scientific event.
The Wollemi pine is a tall evergreen conifer, reaching heights of up to 130 feet. Its mature bark possesses a distinctive knobbly appearance, often described as resembling bubbling chocolate. The tree’s unique branching pattern prevents the formation of lateral branches from the main framework. Similar to the monkey puzzle, its leaves are arranged spirally and flattened in rows, making identification relatively easy. During winter dormancy, the terminal buds are protected by a white resinous cap, believed to be a key factor in the tree’s survival through ice ages.
Since the initial discovery, two more small groves of Wollemi pines have been located, but the total number of mature specimens remains below 100. Most trees exhibit multiple trunks from the base, with some reaching up to a hundred. This natural coppicing mechanism, a defense against fire and rockfalls, has likely contributed to its survival. However, it has been observed that there is limited genetic variation between individuals, suggesting a clonal origin. Classified as critically endangered, the Wollemi pine is strictly protected in Australia, and any attempts to access its remote location are prosecuted. This measure aims to prevent the introduction of Phytophthora cinnamomi, a damaging plant disease, through human activity. As part of conservation efforts, young Wollemi pine plants have been cultivated and distributed globally. The Mount Tomah Botanic Gardens in the Blue Mountains provides a safe haven for the species, mimicking its natural environment and safeguarding its genetic pool. The Wollemi pine, a living link to an ancient past, stands as a testament to the resilience of life and the importance of conservation.
The Coco de Mer: A Palm of Mystery
Endemic to two tiny islands in the Seychelles, the coco de mer palm (Lodoicea maldivica) is a botanical marvel found only in a handful of locations on Praslin and Curieuse. These towering palms can grow to impressive heights, reaching between 82 and 165 feet. Their massive, pleated, fan-shaped leaves can span up to 33 feet in length. The coco de mer’s most striking feature is its record-breaking fruit, weighing up to 88 pounds and measuring 1.6 feet across. Within these colossal fruits lie the world’s largest and heaviest seeds.
The coco de mer has been shrouded in myth and legend. Sailors once believed these palms grew underwater, while tales circulated of male trees uprooting themselves during stormy nights to reach female trees for pollination. These encounters, it was said, could lead to blindness or even death. The name “coco de mer,” meaning “coconut of the sea,” likely arose from sightings of the massive seeds washed ashore or floating in the surf. Although heavier than water, these seeds can float when fully dried and empty.
Their rarity and suggestive rounded shape made the seeds highly prized, becoming coveted collector’s items. Royalty and nobility adorned their cabinets of curiosities with these unique treasures, often mounting them in gold. Trade in coco de mer seeds is now strictly regulated, requiring permits for sale. Despite its extensive study, the coco de mer still holds secrets. Its immense fruit and seed size are believed to be a result of island gigantism, a phenomenon where isolation leads to increased size. The fan-shaped leaves effectively channel water and nutrients down to the soil at the base, resulting in nutrient-rich stands of coco de mer.
The exact method of pollination remains a mystery, with theories suggesting bees or lizards as potential agents. Coco de mer seeds take six to seven years to mature before falling, followed by an extended period before the cotyledon emerges. This rope-like shoot, reaching lengths of up to 13 feet, is the longest known. It serves to guide the new plant towards the ideal spot for root establishment.
The coco de mer faces threats from harvesting, fires, introduced pests, and human development. Despite planting efforts on nearby islands, the total population remains around 8,000 individuals, placing this botanical phenomenon at risk of endangerment. The coco de mer, with its unique characteristics and enduring mystery, stands as a symbol of nature’s boundless creativity and the delicate balance of life on Earth.
