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Humanity has always made great bets on the creation and maintenance of crops. In the past centuries, plant food served as the main source of nutrition. And now, little has changed in this regard. At the same time, man was never the only consumer of plant food - a whole host of herbivorous pests laid claim to it: from birds and animals to insects. And always had to reckon with this undesirable factor. We managed to fight large pests quite successfully: scarecrows scared away birds, fencing and various types of poison saved animals. But insects - these kings of the world - were ready to fight to the last. And one of the most cruel opponents was and remains the locust.
It was already sore, but one can still recall one of the biblical executions of the Egyptians, when the winged death covered a whole country. Of course, this is a myth, but each myth is based on certain life observations. So we can say that locusts as the most dangerous pest have been known since time immemorial.
To find her in the summer is easy, just walk through a green meadow. Grasshoppers and locusts will jump from under the feet. It is not difficult to determine the latter: insects have sizes from 3.5 to 6.5 cm in length; the body has a green, gray-green color; fenders are greenish or reddish, usually painted with orange dots. Most of these pests are defined as Asian migratory locusts - Locusta migratoria. Its habitat is Australia, Asia, Africa, southern and central Europe. Thus, locusts prefer a dry and hot climate.
The problem, however, is that the past decades have been marked by a very uneven climate: everyone remembers the terrible heat of 2010, and before that - 2000. From the news of those years: farmers of the Volgograd region were left without crops - the locust destroyed all growing crops and cereals, grass, melons - even wormwood! According to the observations of experts, at that time from one to one square meter of crops there were from 1000 to 6000 (!) Insects. Winged death simply covered the earth, giving no chance of fighting it. In 2010, the locust moved even further north - to the Urals and Siberia. Hot weather affected the migration processes and other insects, confusing them.
What you need to know about this adversary in order to defeat him
Locusts are born from eggs around May. From one masonry (egg capsule) up to hundreds of insects come out. They grow for some time as a part of swarm colonies, eating all greenery around them. In mid-summer, when there is not enough food left, the colonies “take to the wing” and migrate to the north and west with huge masses at an average speed of up to two tens of kilometers per hour. Their flight is a pretty formidable sight - flocks of several tens of square kilometers are able to obscure the Sun. In August, the zhor of pests is multiplied; insects begin to lay eggs. An insect digs a groove in the ground and squeezes out eggs in a foaming shell. The shell freezes, turning into a small egg, saving eggs from winter frosts. On top of the egg, it is covered with earth for better preservation. And the process repeats itself again.
Various methods have been tested in locust control. Scientists have long been trying to find a natural predator to destroy these insects. For example, in 1762, lane was brought to the island of Mauritius from India, and already after 8 years the number of locusts sharply decreased. But this was not a universal solution. Moreover, it is extremely dangerous. Recall, at least, how much misfortune the Australians brought about the integration into the local ecosystem of rabbits and toads aha. By the way, at the same end of 2010, locusts in Australia seized territories of half a million square kilometers. There were other well-known cases of a "class struggle" with nature. 70s, China. There was not enough grain in the country, and it was believed that it was the fault of the birds. In particular, sparrows. The Chinese army entered the battle with them, shooting flocks of birds from rifles and rifles. Dead bird was taken out by thousands of trucks. When the birds became fewer, the initiative again turned to the ubiquitous locust, which was left without a natural predator. All this is a reminder of how fragile the balance of an ecosystem is.
A new locust control method
But the struggle still did not stop. The main target was insect masonry - as the most vulnerable objects. Fields and floodplains of rivers, meadows and arable lands were plowed up so that the egg capsules would freeze. In some cases, even shelling of territories with military artillery, burning of discovered swords, and ultrasonic repellers were used. In the affected areas, special trap ditches with shields were dug in order to bring down the locust spreading directions. The achievements of chemistry were also used: pollination of the infected areas with HCH powder, a weak solution of arsenic, calcium arsenic or sodium. The latter compound was often supplemented with water, bran and molasses, turning into a poisoned bait.
Since 1921, V.P. Uvarov was the first to publish an amazing “phase theory” conducted on Asian locusts and Danish filly. Its essence is that these species of locusts are one and the same initial species, and their behavior is largely determined by the density of insect nucleation. The higher the density, the higher the tendency of the swifts to relocate, and vice versa. Moreover, a low population density leads to the emergence of settled mares, and an increased density leads to the emergence of winged locusts. That is, the type and behavior of an adult insect is determined at the stage of its maturation, which means that this process can be regulated. Actually, the used plowing of contaminated lands is a means of reducing the density of locust populations.
Despite significant theoretical and practical successes, pest control remains very intense. The reason for this is the lack of resources: technology, poison, qualified specialists. The difficulty lies in the fact that the breeding sites of pests are huge uninhabited steppe territories, inaccessible areas. Thus, in practice, most often one has to deal with already winged insect armadas of adults, and the success of the struggle depends on the speed of “intelligence”, the speed of decisions and the available “combat” resources.