Residents of Beijing's Chaoyang District should have observed that today's trees are densely covered with caterpillars, and even many leafy trees have become withered, and some trees have been nibbled off, and they are also full of insect filaments, and occasionally walk under the trees, and encounter one or two fallen insects.
This phenomenon is not only seen in one or two trees, nor is it just in Beijing, where many urban trees have recently been attacked by this insect. Even many residents reported that caterpillars burrowed into private cars, corridors, and some residents did not even dare to pass under the trees, because from time to time there would be bugs falling, and even a caterpillar rain would form.
So the question is, what kind of bugs is this, and why are there so many bugs this year?
<h1 class="pgc-h-arrow-right" data-track="28" > American white moth</h1>
In fact, the bugs that have formed webs on the Trees in Beijing are not spiders, but an invasive pest: the American White Moth.
American white moth is native to North America, naturally distributed in the United States, Canada and other places, but because of their adaptability to the environment is very strong, so that in the last century, they began to spread with human transportation to Eurasia, in the 70s of the last century, China first discovered the American white moth, since then, the American white moth has not disappeared in our country.
The American white moth is a completely metamorphosed insect that goes through four stages in its lifetime: egg, nymph, adult, and pupa. Among them, the nymph period of the American white moth is a caterpillar.
Adult period is a white moth, from the appearance, the American white moth is simple and unpretentious, it is difficult to attract people's attention, but their harm is very large, and even called "smokeless fire", this is mainly because they have four characteristics, and these four characteristics have also led to them becoming one of the key pests in China.
The first feature is that "3 generations can be bred in a year", under the right environment, the American white moth can breed three generations per year, of which the first generation occurs in April-May, and the second generation occurs in June-July, which is currently in the high incidence of the third generation of American white moth larvae.
Each female American white moth lays an average of 300-600 eggs at a time, up to 1900 grains, and the hatching rate of eggs is very high, reaching about 93%, plus they have three generations per year, so that if there is no effective control, the offspring after 1 year can reach at least hundreds of thousands of animals, and can eat up a forest the size of a football field.
The second feature is "edible miscellaneous", they can endanger the vast majority of broad-leaved forests and shrubs, flowers, vegetables and crops, etc., in our country its parasitic plants as many as 49 families 108 genera 175 species, the common trees in the streets and alleys are almost all their feeding objects, which also led to once the outbreak, will endanger almost all the trees in the area, so they are gardens, agriculture, greening and other key prevention and control objects.
The third feature is "binge eating", after the eggs hatch, they will begin to spit out a net of silk knots, and then they will start to eat leaf flesh in the net. After entering the 5th age, the amount of food of the larvae increases dramatically, and they are very harmful, and it takes only 2-3 days to even eat the leaves of the entire tree.
The fourth feature is "adaptability", the American white moth can resist the low temperature of minus 16 degrees Celsius, can also resist the high temperature of 40 degrees Celsius, and more importantly, in the absence of food, the larvae can even survive for 10-15 days.
In addition, the American white moth can also spread to the surrounding areas with the transmission of vehicles, expanding the scope of influence. Therefore, the American white moth has become one of the most harmful pests in China.
The reason why there are so many American white moths in Wangjing, Beijing, is because the high temperature and humidity this year are conducive to the growth of American white moths.
<h1 class="pgc-h-arrow-right" Data-track="40" is it poisonous > caterpillar period? </h1>
In addition to harming plants, the American white moth also has a great impact on humans. When the American white moth eats the leaves of the light tree during the caterpillar period, it will go down the tree to find new trees or crops, bringing greater economic losses to the crops.
In addition, in some communities, caterpillars will climb to the surrounding houses and walls after descending the tree, densely packed, walking on the road will step on them, walking under the tree and even experiencing "caterpillar" rain, which is particularly scary.
So the question is, is the American white moth poisonous during the caterpillar period? If I accidentally get crawled by a caterpillar, what do I need to pay attention to?
In fact, the American white moth is not toxic in the body, even in the caterpillar period, it will not cause harm to the human body. However, caterpillars have hairs, and some people may be allergic to the hair of caterpillars, so being crawled by caterpillars will be very itchy, and even red bumps will appear, which requires attention at this time, and even need to go to the hospital for medical treatment when it is serious.
<h1 class="pgc-h-arrow-right" Data-track="45" How to deal with the American white moth >? </h1>
The American white moth is menacing, so how do we deal with it?
Usually, the most common method we use in the face of pests is to spray pesticides, but it is important to know that there are many restrictions on spraying pesticides, such as: ripe vegetables, melons and fruits cannot be sprayed with pesticides, the population flow of street trees is large, and spraying pesticides is more harmful to pedestrians. In addition, pesticides are difficult to spray on the top of trees, so that many American white moths still survive.
However, for some areas that have been affected, in order to reduce the harm, the local area will use low-toxicity pesticides as appropriate, and manually remove egg blocks and remove insect nets.
In addition, the staff will also protect daily, the most commonly used, but also the most pollution-free, is to artificially release the natural enemy of the American white moth: Zhou's wasp.
Zhou's wasp is a parasitic wasp, harmless to humans, but particularly fond of the American white moth, once found in the American white moth, the eggs are laid into its pupae, sucking all the nutrients in the American white moth pupa to develop, thereby eliminating the American white moth.
It is worth noting that the American white moth is very difficult to eradicate, and all we can do is to minimize their number, it is difficult to eliminate them completely, so once we are lax in prevention and control, or the environment is suitable, they will erupt again.
#北京毛毛虫 #