At the time of the handover of spring and summer, the occurrence of garden plant diseases and pests increases, and the prevention and control work is aggravated, which should be closely observed and timely controlled according to the forecast.
1. Chongyang wood brocade moth
Harmful to Chongyang wood, can eat up the whole tree leaves, the insect has the habit of spitting silk drooping, affecting pedestrians. Four generations occur a year, the first generation larvae begin to hatch at the end of April, and the middle and late May is the peak of the hazard, and it is necessary to focus on prevention and control to reduce the population density of the first generation.
Prevention and control methods: use 2.5% high-efficiency cyhalothrin 1000 times liquid, or 1% methyl salt 1000 times liquid spraying, spray in early May, spray 2-3 times, each time with an interval of one week; Or injected with 8% methyl salt avermectin can be solved with tree trunk.
2. Acacia inchworm
It is a gluttonous pest that can eat up the whole tree leaves in a short period of time. Three generations occur a year, and mid-May is the peak of the first generation of larvae. The old larvae of the inchworm need to go down the tree to drill the soil to pupate, so the national acacia with soil layer and ground cover in the lower part is seriously harmed.
Control method: In early May, 2.5% high-efficiency cyhalothrin 1000 times liquid or 48% chlorpyrifos 1000 times liquid was sprayed.
3. Acacia microcurly moth
Harm the national acacia, dragon claw locust, with larvae to eat the base of compound leaves, the leaves wilt and droop after being damaged, fall off in the wind or lose water and dry up, and the phenomenon of withered and bald branches appears. It occurs 2 generations a year, with larvae overwintering in the affected shoots and seeds, and feathering begins in mid-May, with the first generation larvae being the most indestructive.
Control method: the effect of pharmaceutical spray is not good, and sex hormone traps need to be used, hung before feathering in early May, and trapping adult insects.
4. Boxwood silk borer
Harmful to finch tongue boxwood, melon seed boxwood, can eat up the leaves, causing the whole plant to die. Four generations occur a year, overlapping generations, overwintering with larvae, overwintering adults from late April to early May, and hatching of the first generation larvae in early May.
Control method: In early May, 2.5% high-efficiency cyhalothrin 1000 times liquid or 1% methyl salt 1000 times liquid spray.
5. Mesozoa
Blowing woolly bugs that harm the sea tong, the moon season, and the rose often cause the death of the whole plant and the whole piece of the sea tong. There are 2-3 generations a year, with female adults or nymphs overwintering on the branches, laying eggs in April of the following year, the nymphs are in full incubation in early May, and the control period is suitable in early to mid-May.
The purple myrtle, which harms crape myrtle, occurs 3 generations a year, and the first generation nymph begins to hatch in mid-May, and mid-May is the appropriate period for control.
Prevention and control methods: the agent uses a combination of contact agent and systemic agent, and then combines silicone additives to enhance the ductility and permeability of the chemical solution. 48% chlorpyrifos 800 times + 10% imidacloprid 800 times + silicone auxiliaries.
6. Reticulated bugs
The adults and nymphs of the square-winged reticulated bug that harm the leaf suck sap on the back of the leaf, forming many dense white fine spots on the front side of the affected leaf and rust-yellow spots on the back. Five generations occur a year, and overwintering adults crawl out in mid-to-late April to lay eggs. Eggs hatch in early May and the hazard period is until October.
The pear crown net bug, which harms begonia and cherry blossoms, occurs in 5 generations a year, and the first generation nymphs begin to hatch in early May, and the damage period is until October.
Prevention and control methods: the agent is preferably systemic agent, using 10% imidacloprid 1000 times liquid, or 10% acetamiprid 1000 times liquid spraying, spraying every 15 days for treatment.
7. Leaf mites
That is, red spiders, a variety of leaf mites harm large-leaf boxwood, begonia, cherry blossoms, osmanthus, fire thorns, sorrel grass, etc., absorb sap, the affected leaves are yellow-white spots, lose green and white, resulting in a large number of leaves yellow, shedding. Mid-May to early June is the first peak period of pests, the highest density of the insect population, the most serious damage, pay attention to control, especially large-leaf boxwood, begonia, osmanthus flowers.
Control method: spray 10% pyridoxine emulsion 1000 times liquid in early May, spray every 15 days for prevention and control, until late June.
8. Psyllids
Acacia psyllid, which harms Acacia and Xyllice, which harms Qingtong, have entered the peak period of harm since early May.
Control method: use 10% imidacloprid 1000 times liquid spraying.
9. Spotted wax cicada
The pest is mainly Tsubaki trees, which occur once a year, overwinter with eggs, hatch in late April, bloom in early May, and feathers into adults in mid-June. Early to mid-May is the appropriate period for prevention and control.
Treatment: Use 2.5% high-efficiency cyhalothrin 1000 times liquid, or 10% imidacloprid 1000 times liquid spray.
10. Tenniu
In April, the larvae of the longhorn beetle have begun to be active, and the affected trees mainly include acacia, willow, fawu, white ash, apricot tree, pentagonal maple, privet, begonia and so on. The main species of longhorn beetle are bare-shouldered star longhorn beetle, star longhorn beetle, mulberry longhorn beetle, rust-colored grain-shouldered longhorn beetle, cloud-spotted longhorn beetle, etc.
Control methods: use a syringe to inject dichlorvos into the cavity, and then close the orifice with wet mud, which can effectively smoke the larvae of longhorn beetle; Using 3% high-efficiency cypermethrin microcapsule suspension 800 times liquid to spray tree trunks and branches can poison and kill adult insects.
11. Underground pests
From April to May, most of the underground pests rise from the deep soil layer to the near soil surface to harm plant roots, and cockchafer (grub), mole cricket, small ground tiger and golden needle worm are known as the four major underground pests of garden plants. They mainly feed on the seeds, roots, stems, seedlings, young leaves and growth points of garden plants, often resulting in missing plants and broken ridges or poor plant growth.
Among them, grubs have the most garden plant varieties and the most serious harm. Grubs have three instars, overwintering in soil with 3-instar larvae. In April of the following year, the larvae migrated upwards into shallow infestation.
Control methods: irrigate the roots, irrigate the roots with 50% octathion 400 times liquid during the larval blooming period, irrigate once in 8-10 days, and irrigate 2-3 times continuously.
In addition to the above, aphids and powdery mildew should be continuously controlled; The American white moth feathers in early May, and the larvae hatch in large numbers in mid-to-late May, and sporadic areas occur and need to be closely monitored.
