Large-leaved boxwood is a very commonly used greening plant in landscaping, it is not only evergreen in all seasons, lush foliage, and tillering ability is very strong, is a good landscaping and modeling plant in landscaping. It can be widely used as a hedge plant in urban greening, and can also be used as a background material during landscaping, and some large modeling plants will also choose to use large-leaved boxwood.
However, in the process of maintenance of large-leaved boxwood, the incidence of diseases and insect pests is relatively high, such as our common powdery mildew, anthrax, leaf spot disease, boxwood silk borer, red wax borer, etc. are very common diseases on boxwood.
However, in the management process of boxwood conservation, sometimes we will often find that there will be some dense long ovate small white dots distributed on the leaves and branches of boxwood.
<h1 class = "pgc-h-arrow-right" > the long ovate white dots distributed on the trunks of large-leaved boxwood branches and leaves? </h1>
The picture shows the large-leaved boxwood branches and long ovate white dots on the leaves
These long ovate small white dots distributed on the branches and leaves of the large-leaved boxwood are actually a very common shell insect of the boxwood, the guard spear-pointed shield borer.
The guard spear is a kind of insect shell insect, the main harm is the plant of the guard spear family, of which the large-leaved boxwood and the guard spear are the most seriously affected; in addition, in addition, in addition to harming the grasshopper, sometimes it can also harm hibiscus, cloves, camellia, honeysuckle and so on.
Most of the nymphs and eggs of the guard spear-tip shield borer are pale yellow, and the female adults are brown to purple-brown long pear-shaped, about 1.4 mm to 2 mm long; and the densely packed long ovate small white dots on the trunks of the large-leaved boxwood we see are actually mostly male adults of the guard spear tip shield borer.
<h1 class="pgc-h-arrow-right" > What are the hazards of the guard spear arrow-pointed shield borer to the large-leaved boxwood? </h1>
The picture shows the large-leaved boxwood branches and the long ovate small white dots on the leaves
The guard spear-tip shield borer is a species of insect shell insect, which belongs to the stinging pest, mainly in the form of nymphs and adults gathered on the leaves or branches of plants, and survive by sucking the sap of plants.
The plants that are harmed by it will have yellowing and dull leaves in the early stage of harm; in the later stage of harm, the whole plant will be covered with dense insect bodies, and the growth will become weaker and weaker, and then the phenomenon of leaf drying will occur, and even the dry death of the whole plant will occur in severe cases.
Because the spear-tip shield worm is a stinging pest, its secretions often induce the occurrence of coal pollution disease, so that the leaves of the plant are covered with coal pollution, thus affecting its landscape ornamental effect and normal photosynthesis.
<h1 class= "pgc-h-arrow-right" > how to do a good job in the prevention and control of the guard spear and the tip of the shield? </h1>
The picture shows the large-leaved boxwood branches and the dense white dots on the leaves
In order to do a good job in the prevention and control of the spear-pointed shield borer, we must first understand its basic occurrence law and choose a suitable time for prevention and control.
1. The basic occurrence law of the wei spear arrow tip shield silkworm:
The annual occurrence of the arrow-pointed shield borer has a lot to do with the local climatic environment, generally speaking, it can occur 2 to 3 generations a year, mainly in the form of fertilized female adults in the form of overwintering on the leaves or branches of the affected plant, and then laying eggs under the female shell around April of the second spring, and the first generation of nymphs hatches in mid-to-late May and begins to endanger the branches and leaves.
The occurrence time of the second and third generations has certain differences in the north and south regions, and in Henan and other areas, it is generally the incubation period of the second and third generations of nymphs from July to mid-to-late September, because the second generation is extremely uneven in development, so the overlap of pest generations during this period is serious, and it is relatively difficult to control.
After November, the third generation of adults feathers, cross-tails, and then overwinter on the branches and leaves of the plant in the form of fertilized female adults.
2. How to prevent it?
The picture shows the daily pruning of boxwood hedges
(1) Combined with winter shears, cut off the branches that carry the source of overwintering insects.
Since the guard spear-tip shield borer is mainly in the form of fertilized female adults overwintering on the branches or leaves of the affected plant, the best way to prevent it is to combine the winter shears of seedlings in late autumn or early spring of each year, prune the branches and leaves carrying the source of overwintering insects, and then take them out of the park for destruction, which can effectively reduce the source of overwintering insects and reduce the outbreak of insect mouths in the spring of the following year.
(2) Spray the agent and clear the garden correctly.
In the early spring of late February and early March, spraying low concentrations of stone sulfur compounds or other broad-spectrum insecticides before the germination of new shoots of boxwood can effectively eliminate some of the sources of overwintering insects.
(3) Reasonable shearing to enhance ventilation and light transmittance.
In the process of daily management, attention should be paid to the timely shearing of boxwood balls that grow too densely or closed, and strengthen the ventilation and light transmittance of plants, which can effectively reduce the occurrence of insect pests and diseases.
3. How to use the drug to prevent and control the spear-pointing shield worm?
The leaves are female adults and young nymphs of the venom-tipped shield borer
(1) When using pharmacy for prevention and treatment, we must know the best period for medication:
When using the drug, it is best to use the drug mainly in the period of dispersion and transfer of the hatchling nymphs of the spear-tip shield, which is mainly because the hatching nymphs have not yet secreted a waxy layer outside the period, which is fully exposed to our eyes, and the resistance to the drug is weak, and the drug is basically used at this time with very few drugs to achieve a better control effect.
(2) The control of the first generation of hatching nymphs is of key significance to the control of insect pests throughout the year:
In most areas, the spear-pointed shield borer can occur in 2 to 3 generations a year, but in addition to the first generation of development generations is relatively neat, the generations of the 2nd and 3rd generations are not neat, and the generation overlap is serious, which brings a lot of trouble to when we spray drugs during prevention and treatment.
In addition, the number of eggs laid by the guard spear-tip shield borer is also relatively large, and the number of insect populations in each breeding generation is doubling.
Therefore, the first generation of hatching nymphs hatched after wintering is controlled, not only is the selected drug relatively simple, the spraying time is relatively easy to control, and it also plays a vital role in controlling the number of insect populations throughout the year.
(3) Specific medication time:
The picture shows the dense white dots on the branches and leaves
The dispersion and transfer period of the first generation of hatching nymphs: in the Henan region, that is, from late May to mid-june every year. Thiamethoxine, or Avi can be used during this period. Acetamidine, highly potency cyfluthrin. Chlorpyrifos, etc., compound osmotic silicone for spraying, in the spraying of attention to the leaves and branches of the large-leaf boxwood completely sprayed, soon dead angle.
In the second and third generation of nymphs hatching heyday: Due to the uneven generation of the second and third generations of nymphs, the nymph incubation time can last from July to about September, and there may be eggs, nymphs, adults and so on at the same time. Therefore, when spraying agents, we should try to choose agents with a long effective period and strong permeability, such as 22.4% helioethyl ester, or 30% helioethyl ester. Pyridyl ether, 30% spirospirant furazine, etc.
In order to increase the adhesion and permeability of the drug, it is best to combine the auxiliary silicone or orange peel essential oil when spraying the drug.
After entering November: After entering November, the adult insects of the Guard Spear Arrow-pointed Shield Borer begin to mate one after another, and then overwinter on the branches and leaves of the plant in the form of fertilized female adults, at this time, the branches and leaves carrying the insect source can be pruned to reduce the source of overwintering insects in the coming year.
<h1 class="pgc-h-arrow-right" > note here is:</h1>
When using the agent to prevent and control the guard spear arrow tip shield beetle, be sure to spray the front and back of the leaf all wet; and it is best to spray the spray 2 to 3 times continuously, and the interval between each time is about 7 to 10 days.
Well, about the prevention and control methods of the large-leaf boxwood guard spear-pointed shield borer, I will introduce it to you here today.
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