The expansion period is the period of high incidence of diseases and insect pests. Key points of management of apple trees in July.

July is the peak period of flower bud differentiation and rapid expansion of apple trees, and it is also a period of high incidence of diseases and insect pests. The management of apple trees in this period is particularly important, and the key points of management are summer pruning, pest control, topdressing, weeding and drainage.

Apple tree

First, summer pruning: first, for strong branches and long branches, take the branches and open the branches at an angle to ease the growth potential; second, some shaded branches need to be removed; third, the middle of spring shoots and blind joints of spring and autumn shoots should be cut short to promote autumn secondary shoots to form flower buds and form high-quality fruiting branches. Fourth, for the apple trees with too much fruit and the fruit part moved out, hanging branches and top branches are carried out to prevent the branches from breaking, which is beneficial to the growth, development and coloring of apples, and fifth is to pick the heart of Wang slightly to promote its short branches to form flower buds.

Second, pest control: in case of "summer drought", red spiders are prone to outbreak, rampant and can spray 24% spiromites 2500 times; apple woolly aphids occur in serious apple orchards, thinning insect tips, spraying 48% chlorpyrifos EC 1000-1500 times + 25% imidacloprid suspension 2000-3000 times + Ruoshuitong 4000 times mixture control In the initial stage of leaf roll moth and leaf miner moth, you can choose to spray 1000-1500 times of 25% diflubenzuron suspension or 6000-8000 times of 40% thiazuron suspension; peach heart borer should be sprayed on trees when the egg rate reaches 0.5%-0.8%. The commonly used agents are 20% thiazuron EC 2000 times, 5% kungfu EC 2500 times (and control mites), and so on. Continue to do a good job of artificially killing leaf roll moth, boat caterpillar, grasshopper cicada, mulberry longicorn beetle and longicorn beetle; in rainy season, spray 43% tebuconazole 2500 times + 80% mancozeb 1000 times, or 50% quinoline copper 2500 times + rare earth fertilizer 2500 times 1-2 times. Control brown spot, leaf spot, anthracnose, and can also set up black light trapping lights, yellow trapping boards, Lepidoptera insect traps, etc., to trap and kill pests.

Third, topdressing: topdressing apple expansion fertilizer in mid-late July is beneficial to promote new roots, improve leaf function, increase single fruit weight, improve apple quality and yield, enrich flower buds and tree nutrition, and improve tree resistance. lay a good foundation for the high yield of apples in the current year and the harvest in the coming year. Generally, 10 kg of biological potassium of Juhai ®was applied per mu of apple field, and the compound microbial agent of Juhai ®was sprayed twice combined with leaves. At this time, the growth of apple trees stopped slightly, and the new flower buds began to differentiate, which was beneficial to apple expansion and flower bud differentiation, and effectively prevented the occurrence of ring disease, anthrax, leaf blight and brown spot.

Fourth, weeding: weeds are exuberant in July, competing for fertilizer and water, affecting the ventilation and light of apple trees, breeding diseases and pests, and weeding in time. Can cut the lush green grass inside and outside the garden, on the edge of the ditch, on the edge of the garden and by the side of the road, and press it under the tree plate. Apple orchards where artificial grass is planned can be sown during the rainy season. Apple orchards that have implemented artificial or natural grass should be cut in time when the grass grows to 20-30 cm high. It is advocated to cover apple orchards with grass-derived materials such as crop straw or weeds, which can not only reduce the breeding of diseases and insect pests, but also reduce temperature, moisturize and improve soil.

Fifth, drainage: July is the rainy season, with a large amount of precipitation, so it is necessary to prevent flood and drainage, soil and water conservation, wind prevention, and so on. In rainy season, more soil moisture and poor ventilation will inhibit the growth and absorption of apple tree roots. Flat apple orchards can carry out the management technique of "ridging cultivation", that is, the topsoil of 10cm can be pressed into the rows, so that the height difference of 20cm between rows and within rows can be formed, and the topsoil layer under the crown can be increased, which can not only store water, but also drainage and waterlogging, promote the absorption of nutrients, and avoid waterlogging caused by waterlogging. The root necks of waterlogged apple trees were peeled to dry in order to restore their roots as soon as possible.