One of the most common stories about Australian flora and fauna is that it is there - almost everything is poisonous or kills in some other way. But the tree with the scientific name Dendrocnide excelsa is one of those that looks almost innocent, and can cause you indescribable pain.
Dendrocnide, translated as “tree that stings” is an Australian enlarged version of our nettle and of course the sting of this tree is even more painful than modest nettles. However, these trees also come from the nettle family, Utricaceae.Dendrocnide excelsa, the gimpi-gimpi as it is called, is a tree that grows in the rainforests of Quensland. It is not uncommon for them to exist in Queensland signs that alert uninformed tourists eager for adventure to an unpleasant plant. There have also been cases where people have been stuck for 36 hours in intensive care units due to contact with plants of this genus. D. excelsa has other poisonous relatives - Dendrocnide moroides and a slightly less poisonous Dendrocnide photinophylla, as well as three other species of this genus with similar properties. Dendrocnide moroides grows as a shrub up to 3m tall, while D. photinophylla and D. excelsa are large trees, growing up to 30m.
It is believed that these poisonous hairs and needles reach the air during the felling of these trees in order to control their numbers and that, if inhaled, they can cause terrible and unpleasant reactions. That is why workers who deal with this must wear protective equipment.
All of these species have branches and leaves covered with stinging hairs, which are reinforced with silicon. In Dendrocnide excels, these hairs - trichomes are especially deceptive because they resemble a kind of soft wool. However, if you go through its branches and accidentally touch those leaves, tiny innocent-looking needles inject a poison that causes such severe pain that even morphine doesn’t help much. Intense pain lasts for hours, and the pain later appears intermittently even weeks after contact.
According to the University of Queensland, the venoms of these species can be compared to that of spiders and scorpions and it is one of the most poisonous plants in the world along with the "tree of death", Hippomane mancinella.
D. moroides was known to have an active substance, a venom from the leaves of an octapeptide called moroidin, which acts as a neurotoxin. However, it was not clear what the poison was in Dendrocnide excelsa. But scientists from Australia have recently solved the riddle of toxins of this species, publishing a paper in Science Advances. Chemical analysis of the needles with which the poison is injected revealed a previously unknown "family" of peptides. The researchers named these molecules gimpietids after the name for this tree in the native language of gimpi-gimpi.
Further analysis showed that these molecules not only generate pain signals, but also suppress the mechanism that stops these signals. The authors hope that their findings will spur research that would contribute to the development of antidotes for the sting of this tree!
Luckily we are far from Australia but you never know, maybe I will go there for the rest of my life. And imagine this information from our area, the goji plant is recognized worldwide as one of the fantastic plants that cures and helps in the mass of diseases. However, in our area it served as a plant fence from whose branches fences were made and the fruit was considered poisonous and toxic.