During the snail occurrence period, there is much precipitation, long duration and high humidity on the ground and in the field, which is beneficial to the feeding and spawning of adult shellfish and suitable for the occurrence and reproduction of adult shellfish.
2. Ecological environment
Some fields are extensively cultivated, and weeds in fields and roadside ditches cannot be cleared in time. Plant residues are placed on the roadside of fields for a long time, which provides a suitable place for Oncomelania hupensis to survive and reproduce.
3. Farmers don't know enough about snails
Snails are extremely fertile, laying eggs many times in their life, and each shell can lay 30 ~ 235 eggs. It is spreading rapidly and causing serious harm. Most farmers lack the control technology of Oncomelania hupensis, so they can't control it effectively at the right time.
4. Less natural enemies
Poor natural control ability is conducive to the occurrence and spread of Oncomelania hupensis. The main natural enemies of snails are reptiles and lizards, and the natural enemy population is very small.
5. Crop straw is high and difficult to control.
It is difficult to prevent and control corn by spraying after the straw grows tall in the late growth stage. When the sun is shining, snails hide in hidden places such as leaves, so it is difficult to spray pesticides on insects. Snails move, feed on leaves, female spikes and other parts, inhabit and hide under leaves and petioles of plants, and it is difficult to control the hidden snails that are high from the ground when scattering particles on the ground.