Preserved trees in the early spring with the use of lime sulfur

Lime sulfur is a kind of inorganic sulfur that can kill bacteria as well as kill insects. The active ingredient is calcium polysulfide, which has a strong ability to infiltrate and erode the cell wall of the pathogen and the body wall of pests and can directly kill pathogens and pests. Plant safety, no residue, no pollution to the environment, pests and diseases are not easy to produce resistance. The use of lime sulfur in the early spring season can have a multiplier effect on the maintenance and management of the whole year. It is also more economical. The author summarizes the use of lime sulfur and communicates with garden workers.

The preparation method of lime sulfur mixture is very simple. The raw materials for preparation are quicklime and sulfur plus water. The best ratio is 1:2:10. Cooking with a pot or a pig iron is best, and using a copper or aluminum pot will affect the efficacy. When tanning, firstly weigh good quality lime into the pot, add a small amount of water to digest the lime, then add enough water, heat and boil, filter out the slag, and then use a small amount of hot water in advance to prepare a good paste of sulfur Slowly pour in, while stirring, and write down the water level line, then add the fire boiled, start timing when boiling (keeping boiling 40 minutes to 60 minutes), boiled in the loss of water to use hot water to supplement, in the ceasefire Add in the first 15 minutes. When the solution in the pan is dark reddish brown and the residue is blue-green, the fire can be stopped. After cooling filtration or precipitation, the supernatant is the lime sulfur stock solution. The concentration of the stock solution can be up to 20 Baume degrees to 24 Baume degrees. The experienced preparer can dip the liquid to about 30 Baume degrees.

If the amount of use is not large or cannot be self-restrained, the mixture of finished products can be purchased, and the efficacy of the product is inferior to that of retanning.

In the winter or early spring when the new leaves of the garden plants have not yet sprouted, it is the best time to use lime sulfur. The use concentration is 3 degrees to 5 degrees in Baume, after the leaves or during the growth period, the concentration is from 0.1 to 0.3 degrees. Stir before use, must strictly control the concentration, to prevent the concentration of too low results in poor efficacy or too high concentration on the seedlings burns. Low temperature below 4°C in spring, and should not be used when high temperature is above 32°C in summer. Before use, the amount of original solution must be measured with Baume pycnometer, and the amount of diluted water should be calculated according to the required concentration. The formula is: water weight = mother liquor Baume degree / diluted Baume degree-1) x mother liquor weight. In addition, lime sulfur cannot be mixed with alkaline agents such as Bordeaux mixture, oil emulsions, rosin mixtures, and copper preparations, otherwise phytotoxicity may occur. The best use of medication with the use, long-term storage is easy to produce precipitation, volatile hydrogen sulfide gas, thereby reducing the efficacy. Must be stored in the lime sulfur liquid surface sealed with a layer of kerosene.

According to our experience in the conservation of urban garden green space, it is recommended that once every spring in the dormant period of vegetation, spray 3 limestone and 5 Baume degrees limestone to the urban garden plants. After germination, reduce the concentration to 0.1 Baume to 0.3. Once Baumedo sprays, it can effectively prevent or reduce the occurrence of pests and diseases. (Author: Qingdao Development Zone Municipal Engineering Corporation)