Tell me why ragweed will seriously reduce the production of many cash crops and food crops, or even no grain harvest.

Dolphin grass, as its name implies, is a kind of harmful grass, and its ability to compete with other plants for water, fertilizer and sunshine is particularly strong. The ability of ragweed to consume water and fertilizer is more than twice that of field crops and cereal plants, so it can seriously reduce the yield of many cash crops and food crops, and even lose food.

The pollen of ragweed can induce hay fever and bronchial asthma, which seriously harms human health. According to foreign data, if there are 30~50 ragweed pollen in one cubic meter of air, pollen disease can be induced. Ragweed pollen has infected100000 people in the United States, Russia, Britain and Japan with hay fever and allergic asthma, and the condition is almost life-threatening. According to the domestic investigation report, more than 60% of asthma patients in Nanjing are caused by ragweed pollen.

It is not difficult to identify ragweed. It's millet.

In order to protect the environment, we hope that every teenager will actively participate in the beneficial social practice of eliminating ragweed, and love the country, people, hometown, greening and natural environment. There are three main ways to eliminate ragweed. From the end of May to the middle of June every year, ragweed is uprooted before flowering, and then dried and burned. This method is simple and effective. If a large area of ragweed is found, 10% glyphosate can be sprayed, and the killing rate is over 90%. In addition, Russia can successfully eliminate and suppress ragweed by using a beetle that only eats leaves.