A recent flowering event involving a rare species of wild plant at the Kunming Botanical Garden has garnered attention within the botanical community. The plant, known as Tianmu ironwood, is native to Zhejiang Province. After being relocated for protective purposes 34 years ago, it has flowered for the first time.
The flowering of the Tianmu Ironwood is a rare occurrence, with each bloom taking place only once every 34 years. This has led to much fascination and speculation. Is its flowering cycle even longer than the Cycas tree? What characteristics distinguish it from other trees?
To unravel these mysteries, we must delve into the origins of the Tianmu Ironwood.
Native Habitat: A Natural Botanical Garden
Nestled in the northwestern region of Zhejiang Province, Mount Tianmu boasts an exceptional geological landscape and a rich natural environment. Designated a state-level nature reserve, it harbors over 2,000 plant species, earning its reputation as a "natural botanical garden." Among its botanical treasures are four exceptional species, collectively known as the "Tianmu Quartet."
Tianmu Ironwood: A Rare and Ancient Tree
Within the "Quartet," there exists a remarkable tree that stands tall and imposing—the Tianmu Ironwood. Only five individual specimens of this precious tree have been discovered to date, each boasting centuries of existence. The oldest among them has witnessed more than 300 years of history.
In 1927, renowned botanist Chen Huanyong meticulously studied this enigmatic species, which was found exclusively on Mount Tianmu. He bestowed upon it the name "Tianmu Ironwood," a moniker that has endured to this day.
Mount Tianmu Mountain Scenery (Image Source: Tianmu Mountain Scenic Area Website)
The Zhejiang Ironwood, also known as the Mount Tianmu Ironwood and the Bretschneider Ironwood, belongs to the Fagaceae family in the genus Carpinus.
The tree has a majestic appearance, with a trunk diameter exceeding one meter and a height of over twenty meters, showcasing an extraordinary grandeur. The cross-section of the trunk exhibits a light, elegant hue with clearly visible grain patterns. The bark is dark gray in color and has a rough texture, exuding the distinctive natural charm of the Mount Tianmu Ironwood.
The male and female flowers of the Mount Tianmu Ironwood differ in both form and color. The female flowers are a luscious green, ensconced in membranous bracts, while the male flowers bloom in a delicate yellow, arranged in typical catkins. Catkins are a type of indeterminate inflorescence, consisting of dense spikes of unisexual flowers arranged like a dog's tail. They often hang downwards and are most commonly seen in plants belonging to the Fagaceae and Salicaceae families.
Celestial Tree in the Mountains: A Rare and Remarkable Species
The Tianmu Celestial Tree is highly endangered, with only five individuals remaining in the wild. Its distribution is limited to northwestern Zhejiang Province.
Due to its long flowering cycle, which takes over 20 years, this species rarely blooms. Its status as a rare and endangered species has made it a priority for conservation efforts.
The protection of the Tianmu Celestial Tree takes two forms. First, a conservation area has been established in Western Tianmu Mountain to promote natural reproduction and growth. Second, the species has been transplanted to botanical gardens throughout the country. The Tianmu Celestial Tree that flowered at the Kunming Botanical Garden after 34 years is an example of this method.
Ironwood with Remarkable Uses
The Tianmu Celestial Tree belongs to the genus Euonymus, which contains about seven species worldwide, three of which are found in China. The Tianmu Celestial Tree is the only species in southeastern China.
The tree is known for its impressive size and hardiness. It can grow over 20 meters in height and has a trunk that requires two or three adults to encircle. Its strength and imposing presence made it valuable to ancient Chinese people.
In the "Book of Marvels," written during the Han dynasty, it is noted that the Tianmu Celestial Tree was said to grow for 500 years before reaching maturity and having a trunk as hard as iron.
Ironwood (Image Source: China Plant Encyclopedia)
If we were to choose the world's hardest tree, ironwood would definitely rank among the top three.
Ironwood's genus name, "Ostrya" (Latin), literally means "tree with hard wood." Harder than steel, ironwood has a wide range of uses as a raw material for furniture, ships, special construction projects, and aerospace components. According to historical records, the ships used by Zheng He during his seven voyages to the Western Seas were made of ironwood. These ships were not only harder than steel but also impervious to water and fire.
Furthermore, ironwood grows very slowly, often taking centuries to mature and decades to flower and bear fruit. As such, it plays an indispensable role in maintaining the local ecological balance.
For scientists, ironwood is also a living natural history book. By studying it in depth, we can gain insights into the mysteries of the growth and reproduction of local species, which is precisely the scientific value of ironwood.
Flowering of Ironwood Varies by Region
Some may wonder if the ironwood tree that flowers every few decades is the same as the one mentioned in the Chinese proverb, "When the iron tree flowers, a mute will speak."
The answer is yes and no. The two trees are not identical, but the one that is outmatched is the iron tree.
Cycads vs. Ironwood
Cycads and ironwood are distinct plants.
Cycads
Cycad Blooming: A Tale of Time and Place
How often does a cycad bloom? The answer depends a lot on where it lives. Cycads are tropical plants that love warm, humid climates, so temperature plays a big role in when they bloom.
In the tropics, cycads can bloom almost every year. In subtropical areas, they might bloom every few years. But in temperate regions, it's a rare sight, maybe only once every few decades.
But with better care, cycads in southern areas can bloom every year from June to August, and their flowers can last for a month.
Some people think the saying "When a cycad blooms, a mute will speak" probably came from northern China, where cycads bloom so rarely.
Scientifically speaking, cycads like the King Sago Cycad can take decades to bloom, unlike cycads that bloom annually.
The King Sago Cycad at the Kunming Botanical Garden that bloomed after 34 years is a reminder of the resilience of life and the wonders of nature. Let's celebrate this miracle of life and look forward to more natural wonders from the King Sago Cycad.
