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Written by Seven Kings
If you touch it gently, it can hurt for a long time, which is the description of "love flowers" in Jin Yong's novel. I didn't expect such plants in the world.
In Australia and Southeast Asia, there is a type of tree skill tree that hurts, with a full glitch. This type of tree is called a stinging tree.
Thorn trees are plants of the genus Hemp tree in the nettle family, and they belong to the same family as urtica dioica, a commonly seen in Eurasia. Of all the thorn trees, the most painful one is called the dendrocnide moroides, which is also known as the most painful tree in the world, the suicide tree.
Dendrocnide moroides Image credit: wikipedia
The common name of the golden bark tree, gympie gympie, was taken by gold diggers in the small town of gympie in the 1860s. The golden bark tree looks harmless to humans and animals, and even a little cute, because its leaves are more loving to humans than to love. However, if you look closely, this "heart" is very large, can be 50 cm wide, the "heart" is sawn, the color of the "heart" is also dark green, and the top is a burr that makes people worse off than dead when they touch it, and the original is sad.
Heart-shaped leaves of the golden bark tree. Image source: wikimedia
So, how painful is the golden bark tree?
According to the account of Marina Hurley, a researcher at the thorn tree, the thorn of the thorn tree dendrocnide photinophylla has felt like being stung by 30 bumblebees at the same time, but compared with the golden bark tree, the former is simply not worth mentioning. Being stung by a golden bark tree feels like soaking in sulfuric acid and sitting in an electric chair at the same time. According to Hurley's experience, pain is still on the one hand, and after being punctured, the lymph nodes in the arm socket will also swell, lasting from 1-4 hours, bringing a second pain.
In 1963, Ernie Rider, a ranger at the Queensland Parks and Fields Service, was slapped all over his body by a golden bark tree, and for the next three days he was so asleep that the pain lasted for two years, and recurred every time he took a cold shower, and nothing could relieve the pain. Until now he believes that when it comes to hurting people, "nothing compares to a golden bark tree." ”
A soldier named Cyril Bromley recalled accidentally falling on a thorn tree in 1941 while passing the Barron River in northern Queensland. Later, because the pain was too much to bear, the hospital tied him up in bed for 3 weeks. He remembered that an officer accidentally wiped his butt with a golden leaf when he was untied at night, and then shot himself directly because he could not stand the unspeakable torture.
Many people develop severe allergy symptoms after being stabbed. Les Moore is a researcher at the Commonwealth Scientific and Industrial Research Organisation (CSIRO) in Australia, and he and Thorn Tree met unexpectedly while doing field research in Battle Freer Mountain. He recalls that when he first met, the thorn tree was really hot eyes, "like someone pouring acid in the eyes." He then developed anaphylactic shock and it took two days for his vision to return. His tongue and mouth were swollen, breathing was difficult, and his entire head was swollen into a sweet potato state.
Some animals, such as horses and dogs, die when they come into contact with the plant. According to the earliest records of the golden bark tree in 1866, a .c. macmillan in northern Queensland, Australia, noted in a report that his horse went mad after being punctured by a thorn tree and died two hours later.
A golden bark tree with fruit hanging from it.
Even if you don't touch the golden bark tree, it is risky to watch it up close.
In 1963, researcher W. V. Macfarlane recorded: "The nasal mucosa is also affected by dust on the leaves of the Golden Book leaves. You'll sneeze at first, your airways will hurt for the next three hours, and then you'll have a sore throat for another 26 hours. The nose will continue to run a nose for two days. Over the next 10 days, the nasal mucosa will be mixed with blood and juices will fall off. ”
What's even more peculiar is that the golden bark tree will only make people worse off than dead, but it will not really make people die, because the thorn tree does not cause direct damage to human tissue. In the literature, there is only one case of death caused by thorn trees. In the 1920s, Dutch botanist HJ Winkler recorded a death caused by a thorn tree during an expedition to New Guinea.
Researcher Marina Hurley and colleagues wore medical masks and protective gloves when exposed to golden bark trees.
It is very difficult to treat the pain caused by the golden bark toxin. In addition to the use of opioid analgesics, wounds can only be treated with dilute hydrochloric acid and hair removal cream. As a result, Australian rangers, loggers and researchers who work in forests infested with golden bark trees also need to bring thick gloves, medical masks and antihistamines just in case, and masks need to be replaced frequently. In Queensland, where goldbark trees are infested, you can also see roadside goldbark tree warning signs.
Roadside warning signs can be seen in Queensland: "Thorn trees can cause severe pain, please seek medical assistance immediately after being stabbed". Image credit: (doi) 10.1126/sciadv.abb8828
This terrible plant also attracted the interest of the British military.
In 1968, the British military and public health research institute, which secretly developed chemical weapons in Bolton Down, England, commissioned Alan Seawright, a professor of pathology at the University of Queensland, to collect samples of golden bark trees. It is not known whether britain has successfully used goldbark trees to create large-scale chemical weapons that hurt people.
In fact, human research on the venom of the golden bark tree has been minimal, and much of the research before the 1960s relied on samples taken earlier.
What is certain is that the unpleasant substance comes from the thorns on the leaves, stems and fruits of the golden bark. In addition to the roots, the golden bark tree has this kind of thorn hair all over its body.
Thorny hairs of the golden bark tree
This type of spiny hair is called trichome, which is mainly made of silica and can be easily worn into ordinary clothes. This spiny hair is very fine, so it is difficult to remove.
The trichome of the golden bark tree. Image credit: institute for molecular bioscience, the university of queensland
The spiny hairs are topped with a ball, and when touched, the ball falls off, and the hairs underneath penetrate the skin, releasing the venom inside. Even with a gentle sweep, these thorns can burst into the soul, making people feel painful and doubt life.
And because the human body cannot decompose silica, the thorns that penetrate the skin will occur from time to time. When pressed or stimulated, the spiny hairs release venom again, and the pain of the drill heart will strike again.
Golden bark trees can grow tall. Image source: australiangeographic
But what is the substance of the golden bark tree that hurts people?
In 1985, chemist T-W Christina Leung and colleagues at the University of Cambridge first discovered moroidin, a relative of the thorn tree, the raportea moroides. Later studies found that the leaves and trunks of the goldenbark tree also contain this toxin, so many people believe that moroidin is the ultimate cause of the pain of the goldenbark tree.
But in reality, the toxin doesn't cause great pain: injections of 10 micrograms of pure moroidin cause less pain than 1 microgram of goldbark leaves. So recently some researchers at the University of Queensland in Australia have studied the venom of the golden bark tree again.
In 2020, a study they published in Science Advances found a new toxin: gympietides, which are more painful than moroidins.
The toxin bears a striking resemblance to the venom in another, a super-human-hurting animal, the snail. But isaac chiu, a neurobiologist at Harvard University, believes that there are far more toxins in the goldenbark tree than these two, and more painful substances may be found in the future.
A heart-wrenching animal snail. Image source: wikipedia
The toxin of the golden bark tree is not only mysterious, but also very stable, and it has been toxic for decades. According to Hurley, the samples of thorn trees collected by the Scientific and Industrial Research Organization of the Commonwealth of Brisbane in Australia in 1910 can still sting researchers today.
The golden bark trees preserved by the Scientific and Industrial Research Organisation of the Commonwealth of Brisbane, Australia, were collected more than 100 years ago and can still be pierced today.
Humans and animals brought by humans avoid thorn trees, but unexpectedly, the leaves of golden bark trees often have dense holes. What biological path is so wild that even the golden bark tree can bite?
It turned out that the golden bark tree left the arrogance to the immigrants and the reservedness to the natives.
In fact, there are still many creatures that love to eat the leaves of the golden bark tree. Native Australian mammals, such as the green-ringed possum (pseudochirops archeri) and the swamp forest kangaroo (thylogale stigmatica), love to nibble on goldbark trees. Swamp forest kangaroos can eat a large leaf in one night.
Birds also eat the berries of the golden bark tree and another thorn tree dendrocnide cordifolia. By the way, the berry of the golden bark tree can be eaten by people, but it must be dehaired first. Given the dull taste of this berries, it is dangerous and not worth having for foodies.
The fruit of the golden bark tree. Image source: wikipedia
Insects can also crawl between the spines without being affected. The native Australian beetle prasyptera mastersi can walk freely between the spiny hairs, nibbling on leaves that are not covered by thorn hairs. Grass borer prorodes mimica can also make nests on the leaves.
Australia's native beetle prasyptera mastersi is not afraid of the golden bark tree.
In fact, the leaves of the goldenbark tree, as well as other thorn trees, are very nutritious and rich in nitrogen and calcium. If you know how to deal with those thorny hairs, eating gold-skinned leaves is the right choice, no wonder their leaves are always covered with wounds.
Similar to the golden bark tree, many plants in the nettle family are quite tasty. In Europe, the leaves of nettle, a close relative of the thorn tree, are also often made into tea or cuisine, which is called nettle tea.
Nettle, a relative of the golden bark tree, although also pierced, can be made into tea leaves. Image credit: pixabay
Since goldenbark and other thorn trees are harmless to many native species, what exactly is their stinger useful?
There are more spiny hairs on the young leaves of the thorn tree, and as the leaves age, the density of the spiny hairs also decreases, which means that the thorn hairs may be used to protect the delicious young leaves. One possible explanation is that the spiny hairs were prepared for certain extinct ancient mammals, such as diprotodonts.
The burrs of the golden bark tree and another thorn tree, dendrocnide cordifolia, also spontaneously shed, which may also be a defense mechanism: the falling thorns can help it draw a "boundary" near the tree, allowing it to have more room for growth.
More importantly, such a hot-eyed plant is already an endangered species in New South Wales, Australia, and it seems that their stingers are not a universal weapon. What evil eye can the golden bark tree have, it just wants to live a little longer.
Golden Bark Tree: You don't hurt, it's a matter of me.