What are bean worms and what garden plants do they harm?

1. What are bean worms?

Bean worms refer to the larvae of the bean moth, also commonly known as bean cicadas, bean dan, etc. They specifically belong to the Sphingidae family of the Lepidoptera order, and their growth cycle is one generation per year. Its larvae are generally yellow-green and about 90mm long. There is a yellow-green protrusion on the head, 3 pairs of thoracic legs, 1 pair of caudal legs, and 4 pairs of abdominal legs. The tail is yellow-green. In addition, it occurs mainly between late July and early to mid-August and is mostly related to precipitation.

2. Which garden plants will be harmed?

Bean bugs mainly parasitize on plants such as mung beans, soybeans, locust trees, and acacia trees, which means they will harm these plants. The distribution areas are generally in the Huanghuai River Basin, the Yangtze River Basin and South China. Adult insects are mostly nocturnal and hide during the day, resting in the middle of crop stems during the day and becoming active again in the evening. Some also like to suck nectar and are attracted to black lights. In addition, it occurs more frequently in low-lying areas with dense plant growth, fertile soil and low terrain.

3. How to prevent and treat

Agricultural control methods can be used for prevention and control. The soil should be deeply plowed to eliminate overwintering insect eggs. We also need to change our farming methods, such as intercropping rapeseed to control soybean pests. It can also be captured manually or sprayed with medicine. The drug of choice can be DDT, malathion or carboplatin. It is best to spray the pesticide in the afternoon for better results.