Prevention and control of red spiders should be emphasized during the rainy season.
The editor will explain the planting content of the flower clinic for you. Prevention and control of red spiders should be emphasized during the rainy season. Next, the editor of this site will introduce to everyone.
For the control of red spider pests, attention should be paid to observation in daily life. When leaf color is abnormal, the back of the leaves should be carefully checked. If many leaves are infested, the medicine should be sprayed early.
Red spiders are small in size and are not easily visible to the naked eye under normal circumstances. A dissecting microscope or magnifying glass can be used for observation, or a piece of white paper can be taken first, then the affected leaves or branches can be tapped on the paper a few times to check if there are "small black spots" moving on the paper surface, which can be identified. Additionally, you can check if there are small spots on the leaves that have been damaged. If there are more than 10 pests on an average leaf, it will affect the growth and greening effect of the plant, and measures should be taken for prevention and control.
(1) In early spring or winter, spray a 3-5 degree lime sulfur solution on the plants, and add 0.2% to 0.3% laundry detergent to enhance the spreadability of the medicine, which can kill overwintering eggs or adult mites and reduce the pest density. Before germination, spray an 800-fold liquid of 20% miticidal wettable powder, 5% to 6% anthracene oil emulsion, or 5% heavy oil emulsion to kill overwintering eggs.
In the late March to late April when tree buds are germinating, spray a 0.5-1 degree lime sulfur solution, or 1000-fold liquid of 4% omethoate emulsion to control newly hatched larvae and adult females emerging from hibernation.
(2) From late April to early May, during the peak period of overwintering eggs hatching, use a 5-10-fold liquid of 40% omethoate emulsion or a 30-fold liquid of 18% highly penetrable omethoate emulsion for root application or trunk painting.
(3) During the period of red spider damage, apply phosphamidon and other pesticides to potted flowers and landscapes, with the amount of medication depending on the size of the plant. After applying the medicine, sufficient water should be poured to enhance the efficacy. Alternatively, directly pour the omethoate emulsion or other systemic insecticides. However, all applications should be kept away from water sources to avoid pollution.
(4) For most red spiders, the climate is a high-temperature activity type, and dry and hot weather conditions often lead to a large number of occurrences. Therefore, timely prevention and control should be carried out before the arrival of high-temperature and dry seasons. Any period of high-temperature and dryness can lead to the proliferation of red spiders, and inspection work should be done, with timely application of medicine based on the inspection results, and the control should be consolidated 10-15 days after the application of medicine.
In the period of mass occurrence, you can spray a 500-600-fold liquid of 20% dicofol emulsion, 2000-fold liquid of 20% fenvalerate emulsion, 1500-fold liquid of 5% hexythiazox emulsion (ineffective on adult mites), 1500-fold liquid of 50% chlorpyrifos emulsion, 1500-fold liquid of 40% water-soluble phosphorus emulsion, 1500-fold liquid of 40% omethoate emulsion, 2500-fold liquid of 10% pyridaben emulsion, 1500-2000-fold liquid of 25% azocyclotin wettable powder, or 3000-fold liquid of 10% diflubenzuron emulsion, etc., and spray uniformly on the tree body, paying special attention to all new shoots to significantly reduce the pest density. To avoid resistance, the above miticides should be used alternately or mixed.
From late May to early June, use the biological miticide Liuyang霉素 (20% compound preparation) at a 1000-1200-fold concentration, or an 800-1000-fold liquid of 20% miticidal wettable powder, to control the first-generation newly hatched larvae, nymphs, and virgin adult females.
From June to July, when there is a large occurrence, spray a 4000-fold liquid of 73% propargite emulsion, 4000-fold liquid of 40% mitacloprid emulsion, or 2000-3000-fold liquid of 20% pyridaben wettable powder. Generally, spray once every 10 days, alternating and continuing for 3-4 times. When spraying, make sure to spray the lower and back parts of the plant and keep it uniform. Do not continuously spray the same pesticide to avoid resistance.
To avoid resistance in red spiders, it is best to alternate with organophosphates and other miticides, and ensure that both sides of the leaves are treated to ensure control effectiveness. Chemical pesticides can easily cause resistance, making control difficult, so it is important to rotate the use of pesticides and not arbitrarily increase the concentration and frequency of application. Choose high-efficiency and safe pesticides and target the vulnerable stages of the pests. To consolidate the efficacy, spray every 15-20 days to completely control the occurrence of mites. Using two or more pesticides simultaneously or alternately can enhance the control effect on resistant mites.
(5) Potted plants can be treated with furadan granules once in March and July each year, with 5-7g for large pots (with a diameter and height of 30 to 40cm) and an appropriate amount for smaller pots. Make 3 to 4 holes diagonally in the pot, 3 to 4cm deep, and bury the medicine in the holes, or mix the medicine with the soil during potting in spring. This medicine is highly toxic and has a long residual period, remaining in the soil for about 30 days and entering the plant's branches and leaves with water, causing the red spiders to die after absorbing the sap. Note: The fruits of potted plants should not be eaten to prevent poisoning. For larger potted plants, such as lucky bamboo, if red spiders are found, a smoke fumigation method can be used, placing a plate of mosquito repellent incense containing pyrethroids in the pot, covering the entire plant with a plastic bag, and tightly sealing the pot opening. After about an hour of fumigation, both adults and eggs can be killed.
The above () introduces the specific methods for preventing and controlling red spiders during the rainy season, hoping everyone will like it!