Application and Popularization of Chemical Weed Control techniques in Seedling raising of Cunninghamia lanceolata

Application and Popularization of Chemical Weed Control techniques in Seedling raising of Cunninghamia lanceolata

Cunninghamia lanceolata belongs to gymnosperms, Cunninghamia lanceolata, Cunninghamia lanceolata, evergreen trees, with a long history of cultivation, fast growth, good quality, straight wood texture, uniform structure, no warping and crack, excellent corrosion resistance and insect resistance. Therefore, it is widely used in many fields, such as bridge, construction, furniture, shipbuilding and so on. Therefore, the seedling cultivation of Cunninghamia lanceolata is particularly important. in the process of seedling cultivation, weed control is an important guarantee for the healthy growth of Chinese fir seedlings.

1 points for attention in chemical control of weeds

In the process of raising seedlings of Cunninghamia lanceolata, various chemicals are mainly used to control weeds, and the use of chemicals must follow the relevant application regulations in order to achieve the purpose of weed control reasonably and economically on the premise of ensuring safety.

1.1 method of application

Reasonable application method is the basic guarantee to ensure the best effect of herbicides. After sowing and before seed germination, the more appropriate soil treatment methods are poisonous soil method and spray method. In the seedling stage, when the herbicide used is harmful to Cunninghamia lanceolata seedlings, the poisonous soil method should be used, and if there is no damage, foliar spraying can be used. No matter which method of application is adopted, it is necessary to ensure that the agent is evenly sprayed on the weeds to ensure a good effect of weeding. When spraying the agent by the poisonous soil method, the fine soil is screened to ensure the appropriate humidity, the EC can be diluted with water before it can be mixed with the fine soil, and the powder can be mixed directly. When using the spray method to control weeds, the amount of water, dosage and containers should be selected according to the actual needs to ensure the effect of pesticide application.

1.2 Drug dosage

Although herbicides have a good control effect on all kinds of weeds, an appropriate dose of herbicides is a necessary condition to control weeds. Too much or too little herbicides not only can not exert the effect of weeding, but also have adverse effects on the growth of Chinese fir seedlings. In addition, the efficacy of some herbicides must be in the prescribed environment and dose range to achieve the best efficacy, and temperature will also have an effect on the efficacy of herbicides.

1.3 time of application

Weeding Chinese fir seedlings before sowing and after seedlings growing is the guarantee of normal growth of Chinese fir seedlings. In addition, the characteristics of Chinese fir seedlings are different in different growth periods, and the demand for herbicides is different in different growth periods, so herbicides should be chosen according to the actual situation. When the herbicide is used once, after the herbicide efficacy period ends, if there are more weeds sprouting and growing, it is necessary to choose other herbicides to control weeds in time.

(2) the techniques of controlling weeds during the seedling period

In the process of raising seedlings of Cunninghamia lanceolata, in order to prevent the growth of weeds from affecting seed germination, weeding should be done before germination. The commonly used herbicide is desmodium, which has low toxicity and little harm to Cunninghamia lanceolata seedlings. At the same time, it is easy to be decomposed in the sun and has high volatility. The use of desmodium herbicides plays a significant role in the control of most broad-leaved weeds such as Setaria angustifolia, Chenopodium and some dicotyledonous weeds. In general, the period of validity of the herbicides can reach 50 days. The effects of desmodium in weeds are as follows: after entering weeds and other plants, desmodium can effectively inhibit the cell division activity of plant meristem, hinder the normal growth of weed young roots, and accelerate the death of weed seedlings. Before actually spraying desloramine, first of all, the Chinese fir seedbed should be leveled, sprayed with 800-fold solution of desloramine, sprayed evenly on the seedbed, and then covered with yellow soil and kept for 3 days before the seeds of Cunninghamia lanceolata could be sown into the seedbed.

(3) Weed control techniques during seedling growth.

After the seeds sprouted and grew into seedlings, it was usually about 50 days after sowing, when the weed control effect of desmodium had basically declined, and the weeds began to emerge again to compete with Chinese fir seedlings for nutrients. Therefore, in order to control weeds on the basis of protecting the seedlings of Cunninghamia lanceolata, the commonly used and effective herbicide is ethoxyfenoxane, which is a contact herbicide with low toxicity. The necessary condition for ethoxyflurane herbicide to exert its herbicidal effect is sufficient light, which has a very significant control effect on grasses, sedges and annual broad-leaved weeds. The spraying frequency depends on the growth of weeds. Usually, weeds can be basically removed by spraying 2 or 3 times.

Weed control techniques in 4-step ditches

For all kinds of weeds growing in trail ditches, killing herbicides can be used without considering the adverse effects of herbicides on the growth of Cunninghamia lanceolata. The commonly used agents are Roundup, glyphosate, paraquat and so on. In the specific spraying process, in order to keep the nozzle low, the spraying agent should be shielded to prevent accidental spraying on Chinese fir seedlings, causing drug damage to Chinese fir seedlings and affecting the normal growth of Chinese fir seedlings.

5 conclusion

The use of chemical herbicides to control weeds of Cunninghamia lanceolata not only has good weed control effect, but also has low economic cost and quick effect, so it is a very suitable weed control method. However, in order to ensure the weeding effect of chemical herbicides, great attention should be paid to chemical selection, application method and dosage, application time and so on.