In the face of weeds, the first way that everyone thinks of is the herbicide , then how can the herbicide be used? The hot net Xiaobian tells you that the dosage and timing of the herbicide is the key, if you can't grasp the herbicide The dose and timing are likely to be counterproductive. Chemical control is the use of crops and various pests to the sensitivity of a drug, using a dose that can inhibit or kill the pest without affecting the normal growth and development of the crop. Obviously, the greater the difference between crops and pests, the wider the variety and dosage range of agents that can be used. Relatively speaking, pesticides should distinguish between plants and animals. Bactericides distinguish plants and fungi. They are spanned by two biological circles. The difference in morphology and physiology is huge. Therefore, the doses of insecticides and bactericidal agents are mainly referred to. For doses that are effective for pests, some farmers increase the concentration, and even multiply the concentration without phytotoxicity. However, herbicides are to distinguish between crops and weeds, they are all plants, and even plants of the same family, such as wheat field control wild oats, which belong to the family Poaceae, which is destined to be applied at a very high dose of herbicides. Strict and expressed in terms of the effective dose of the agent used per unit area (insecticidal or bactericidal agents are sometimes expressed in terms of the concentration of the drug solution). The lower limit is the effective dose for weeds and the upper limit is the safe dose for the crop. Weighing is not accurate when using the drug. If the dosage exceeds the specified dose or when spraying with a motorized sprayer, the nozzle will not oscillate unevenly, the nozzle will be stagnant, the re-spray or the machine will be left behind. Secondly, farmland weeds and crops are in a competitive relationship, and the growth stages and processes are similar. Whether using the difference or the time difference, favorable application time is limited. Taking pre-emergence soil treatment such as dol and acetochlor as an example, although the pot life is long, the application time is only before and after the crop is planted, and the weeds have not been unearthed. Once the weeds emerge and re-medicate, it will not only have no effect, but will also harm the crop. To this end, it is necessary to arrange the farming, fertilization, sowing, and spraying of agricultural materials, and interlocking. For the treatment of stem and leaf, it is also necessary to use it for a certain period of time. For example, the use of nicosulfuron in corn fields can control a variety of single and double cotyledon weeds, but only in the 3-5 leaf stage of maize, 2-4 leaf stage of annual weeds, and 6 years before perennial weeds. Apply at a height of about 5 cm. Because it can only be inhibited or killed after the weeds have absorbed a certain dose. The grass is small, and the received medicine is small; or the grass is large, and the resistance (resistance) is increased, which will reduce the herbicidal effect. In addition, in the case of drought, the weeding effect will be reduced due to the emergence of weeds. Therefore, when to use the herbicide depends on the law of weeds. The use of pesticides is highly effective. More pesticide knowledge , please pay attention to China Pesticide Network (Source: Agrochemical Investment Network) Reflecting Mirror include metal mirrors and dielectric mirrors. Reflecting Mirror,Silver Plated Mirror,Silver Plated Compact Mirror,Silver Flash Mirror Coating Changchun Champion Optics Co.,Ltd , https://www.champion-optics.com