If you want to be beautiful in the city, you can't leave all kinds of green trees. In recent years, some netizens often spit out some green trees, and some netizens directly summed up four kinds of green "harmful trees". Take a closer look at the sins of these four trees. It's not light, but why not ban it completely?
I. Poplar
The most famous poplar is its catkin, which is a female tree called Populus tomentosa. Every April and May, some areas will be covered with white catkins. If a gust of wind hangs on the grass, it is like a light snow.
It looks good from a distance, but it's really nothing compared to its "sin"
1, causing a fire, the ignition point of catkins is extremely low, and it is easy to be ignited by a cigarette butt. In recent years, because there are many catkin fires, it has caused great harm to people's lives and property.
Only in recent days, fires caused by burning catkins have occurred in Yucheng, Shandong Province, Kaifeng, Henan Province, Botou, Hebei Province, and a fire brigade in Xuzhou, Jiangsu Province put out 13 catkins-caused fires in one day.
2, causing allergies, Yang Xu will enter the human body with people's breathing. Some people with allergies are prone to allergic reactions, showing symptoms such as cough, tears and runny nose. In severe cases, it will cause fever, laryngeal edema, even suffocation and loss of life.
3, affecting traffic safety, flying poplars will seriously hinder people's sight, and poplars entering the car will easily block all kinds of filter elements, increase the cost of car use and increase the probability of traffic accidents.
Second, willow trees.
Although there are many poems describing willow in ancient poetry, many poets praise it.
But now the willow has become a harmful tree, because the seeds of the willow have white fluff. If the local willow planting is relatively large and concentrated, a lot of catkins will be scattered in the air. The harm of catkin is the same as catkin, which will cause fire, allergic reaction, traffic accidents and so on. So catkins and catkins are generally referred to as catkins.
Third, the French phoenix tree
There is also a nice name Platanus acerifolia. According to the number of balls, there are some Platanus acerifolia, some Platanus acerifolia and some Platanus acerifolia, but no matter how many balls are imported from abroad, one ball originated in North America and is called Platanus acerifolia. Qiu Er is native to Britain, also known as the British phoenix tree; Sanqiu originated in southeastern Europe, so it is called French phoenix tree.
Although Platanus acerifolia is mainly planted in China, we call it Platanus acerifolia because it was introduced to Shanghai by the French.
The biggest problem of Platanus acerifolia is that in April and May every year, its cones explode to spread seeds, usually carrying Mao Mao. These seeds fly with the wind and get into people's clothes, eyes and noses.
Although this kind of "wool" will not increase the fire incidence like catkins, it will also affect the sight, cause traffic accidents and endanger people's health.
Four, Luan tree
Although Luan tree says it won't cause fire and endanger people's health, it is also annoying as a greening tree. Its problem is that you can't put anything under the tree or park your car every spring, because it will "pee". If you park your car in Luanshu the next night, you will find the car covered with "oil spots" the next morning. If people stand under a tree, they will feel light rain. More importantly, this "oil point" is very important.
Of course, these small oil spots are not really "urinated" by Luan trees, but because Luan trees are very prone to aphid disease. Aphids feed on the sap of Luan tree. After the aphid sucks the juice, the sugar in the juice will be excreted by the aphid. If there are a large number of aphids, these sugars will accumulate into small drops and eventually fall to the ground and stick to the car. Although the sugar excreted by aphids is harmless to human body, it is annoying enough, and it is difficult to clean the car.
Since these four trees are so annoying, why not just ban them? This will start with their advantages.
Willow occupies an important greening position in many places. It is a standard primrose tree and takes the lead in sprouting and growing leaves every year. In addition, the maximum length of willow can reach 30-40 meters, and the crown can reach 6-7 meters. The shading effect is very good, which can effectively reduce the direct sunlight, reduce the environmental temperature and improve the local microclimate of the city.
Although willow will produce catkins, causing great harm, its ecological values such as cooling and humidifying, sterilization and disinfection, absorbing harmful substances, releasing oxygen and carbon fixation can not be ignored.
According to the research, a willow tree with a DBH of 20cm can absorb 28 1 kg of carbon dioxide, release 204kg of oxygen and retain 36kg of dust every year, and the annual economic benefit of a willow tree is as high as 1350.6438+07 yuan.
However, a poplar with DBH of 20 cm can absorb carbon dioxide 172kg, release oxygen 125kg and retain dust 16kg a year, and the economic benefit is 935.87 yuan.
Now the problem of catkins has attracted the attention of relevant departments, and they have begun to find ways to solve it, such as replacing female catkins with male ones, grafting and improving trees with serious catkins, reducing catkins, spraying catkins with dust trucks and reducing the amount of catkins in the air.
Platanus acerifolia can be regarded as the well-deserved "king of street trees" in the northern hemisphere. It has the advantages of rapid growth, short crown forming time, good shading effect, developed root system, cold tolerance and barren resistance, strong ability to resist pests and diseases, no need to apply pesticides, and strong ability to absorb carbon dioxide and harmful gases.
At present, the problem of "hair loss" of French phoenix tree is mainly to cultivate phoenix tree varieties with less hair loss, and then graft the phoenix tree varieties with less hair loss to the original trees, thus reducing the problem of hair loss of French phoenix tree.
Although Luan Shu has a big problem of "peeing", we can't deny its advantages. You can enjoy leaves in spring, flowers in summer and fruits in winter. It is a veritable "beauty of the four seasons" tree.
Luan tree can also absorb a large number of harmful dust particles, and has strong resistance to harmful gases such as carbon dioxide and ozone, which is very helpful for the control of urban smog.
In addition, Koelreuteria paniculata has strong adaptability, cold tolerance and salt tolerance, and can also be planted in northern China.
In the face of so many benefits, the small problem of "peeing" can be ignored.
Seeing so many benefits of these trees, are you still willing to ban them? Of course, I also hope that scientists can find an effective way to solve the shortage of trees as soon as possible, so that willow, French phoenix tree and Luan tree can better adapt to the role of green trees.