Deep turning and soil improvement technology of walnut orchard

   deep ploughing is one of the main technical measures for soil improvement in walnut orchards, which is suitable for areas with poor soil conditions. Through deep ploughing, on the one hand, it can store water and preserve soil moisture and improve soil structure; on the other hand, it can enhance the activity of soil microorganisms, accelerate soil ripening and improve soil fertility. Deep ploughing and soil improvement created good growth conditions for the root system and improved the absorptive capacity of the tree, thus promoting the growth and fruiting of walnut.

The picture shows walnut

The most suitable time for    deep ploughing is after fruit harvest and before defoliation. Because it is the peak of root growth before and after fruit picking, the wound caused by deep turning is easy to heal, and some roots can be cut off to stimulate the growth of a certain number of new roots and whisker roots, and the effect of fertilization and irrigation will be better. It can also be combined with green manure and fine stalk in summer to increase the organic matter of soil and improve it.

   deep flip can be divided into expanding hole deep flip and whole garden deep flip. After 2-3 years of planting, the young walnut trees turned outward and expanded the planting holes year by year, until all the trees were turned over, and it generally took 3 ~ 4 years to complete the deep turning of the whole garden. Adult trees dig circular or parallel trenches at the edge of the vertical projection of the crown every year or every other year, with a width of 40-50 cm and a depth of 60-80 cm. The topsoil and core soil are respectively placed on the west side of the ditch, the bottom of the ditch is covered with straw, the soil is backfilled with organic fertilizer, the topsoil is placed on the bottom, the subsoil is placed on the upper layer, and then fully irrigated.

   for long-term extensive management of walnut orchard, if the soil consolidation is serious, the method of blasting and loosening the soil can achieve deep ploughing, which can not only avoid the malpractice of deep ploughing, but also play the role of loosening soil, promoting microbial activity, water conservation, fertilizer conservation and heat preservation, and save time and effort than artificial deep ploughing.

   soil improvement is mainly aimed at sand, clay and saline-alkali soil and other poor soil improvement measures. If the walnut orchard is built on the beach, sand extraction or soil pressing must be carried out. When pumping sand for soil, remove sand 1 meter wide and 30 centimeters deep according to row spacing, replace it with loam of the same volume, and then stir it up and down evenly, with a depth of 50 to 60 centimeters. When pressing the soil, the whole garden generally presses 30 to 40 boxes of loam, and then ploughs or turns deeply to make the sand mix with the soil. Some pure sandy land is clay below 30cm to 40cm. The lower clay is turned up and mixed with the upper sand through deep ploughing. Sandy soil should apply a large amount of organic fertilizer and plant barren-tolerant green manure to improve the physical and chemical properties of the soil. The plough layer is the best way to mix sand and change soil in the clay walnut orchard to increase the soil permeability and improve the fertilizer supply capacity, and at the same time apply more rotten organic fertilizer to improve the soil structure and increase the content of soil organic matter. For the walnut orchard in saline-alkali land, it is necessary to increase the application of organic fertilizer, properly control the use of chemical fertilizer, combined with straw returning to the field, planting salt-tolerant green manure and other methods to reduce the harm of saline-alkali. Increase the application of phosphate fertilizer, appropriate amount of nitrogen fertilizer, little or no potassium fertilizer. Alkaline soil should apply more physiological acid fertilizer to improve soil, such as calcium superphosphate, ammonium sulfate and so on. The salt can be washed with water pressure and alkali when there are conditions.