How to control tree lice?

Tree lice, also known as grass scale, pear round scale, pear round scale, round scale, etc., are widely distributed, mainly damaging pears, apples, etc., but also damaging peach, plum, persimmon and other fruit trees. Generally, female insects are concentrated in branches, male insects are often concentrated on both sides of main veins of leaves, and damaged branches cause cortex cork and phloem, vessel tissue decline. Let's take a look at how to control tree lice together!

harm characteristic

Tree lice are the most common pests on flowers. There are 6 common species, such as blowing scale, camphor mussel round scale, chaff scale, Korean ball scale, mulberry white scale and Kang's mealybug, which often cluster on branches, leaves and fruits. Adults and nymph insert needle-like mouthparts into leaves and branches of flowers to absorb juice, causing branches and leaves to wither, even whole plants to die, and can induce coal pollution disease, which is extremely harmful.

occurrence regularity

Tree lice have 3~4 generations a year, generations overlap, overwintering as nymph and fertilized female on branches, overwintering nymph begins to damage in spring of next year, viviparous reproduction begins in late April and early May, second generation nymph occurs from late June to early July, third generation nymph occurs from late August to early October, and fourth generation nymph occurs in mid and late November. The newly hatched nymph rests under the female scale and soon climbs out to spread harm.

control methods

1, strengthen quarantine: under natural circumstances, tree lice activity is small, its own transmission and diffusion capacity is limited, distribution has certain limitations. However, with the development of production, flower exchange and transportation are frequent, and the opportunities for artificial and long-distance transmission of diseases and insect pests are increasing. Quarantine work stipulates that flowers can be transported without dangerous pests. If pests are found, effective measures should be taken to eliminate them and prevent further spread.

2. Artificial control: In the process of planting flowers, it is found that there are tree lice on individual branches or leaves, which can be gently brushed with soft brush, or cut off insect branches and leaves in combination with pruning. It is required to brush, shear and burn them intensively. Do not throw them away.

3. Use of natural enemies: such as Australian ladybug, red ladybug, golden aphid, soft scale aphid, red-spotted ladybug, etc., which prey on blowing scale, are effective natural enemies, which can be used to control the harm of tree lice and should be protected and utilized reasonably.

4. Chemical control: spray at the peak of nymph according to the occurrence of tree lice. Because at this time most of the nymph hatching soon, body surface has not yet secreted wax, scale has not yet formed, medication is still easy to kill. Spray once every 7~10 days for 2~3 consecutive times. can be sprayed with 40% omethoate 1000 times solution, or 50% malathion 1500 times solution, or 255 imine 1000 times solution, or 50% dichlorvos 1000 times solution, or 2.5% deltamethrin 3000 times solution, but it is best to choose to carry out in the larval stage, when the wax layer has not formed, the control effect is good, if this opportunity passes, it is necessary to use pesticides such as methidophos to control, It can also be controlled by spraying 0.2% detergent solution or 0.3% essential balm.