Reasonable intercropping cultivation model of walnut trees

   intercropping is an important cultivation mode. Reasonable intercropping can make full use of space, land and light energy, and improve economic benefits, especially the early benefits of young walnut orchards.

The species and methods of    intercropping are based on the principle that they do not affect the growth and development of walnut. According to the different types of crops, they can be divided into different models, such as fruit-grain intercropping, fruit-vegetable intercropping, fruit-drug intercropping and fruit-fertilizer intercropping. Suitable intercropping crops should be selected according to local site conditions, management level, and planting and sales habits.

   fruit-grain intercropping is a traditional intercropping mode. Grain and oil crops have the characteristics of short growing season, early maturity and easy farming. Fruit-grain (oil) intercropping can be carried out in plots with good site conditions and high fertility. The commonly used crop types are soybeans, mixed beans, potatoes, rape, peanuts and so on. Walnut can also be intercropped with corn, sorghum and other tall stalk crops when the row spacing is large. Fruit-grain intercropping can effectively promote walnut flowering and increase the yield per plant, because it can promote walnut flowering and fruit setting through deep ploughing, loosening soil, weeding, fertilization and other measures. At the same time, due to the nitrogen fixation of legumes, it can effectively increase the soil nitrogen content and promote the vegetative growth and reproductive growth of walnut.

   fruit-drug intercropping is an important way to improve the economic income of walnut orchard. Because of its high economic value, considerable income and in line with the current national industrial policy, traditional Chinese medicine has become one of the main projects of walnut orchard. The kinds of medicinal materials commonly used in intercropping are Salvia miltiorrhiza, Platycodon grandiflorum, Bupleurum, Radix Isatidis, Radix Scutellariae, Atractylodes macrocephala, Shengdi, Honeysuckle and so on.

   intercropping of fruits and vegetables (melons) is generally carried out in walnut orchards adjacent to towns and under irrigation conditions. Commonly used vegetables are white radish, Chinese cabbage, cabbage, as well as a variety of melons, strawberries and so on.

   fruit manure (green manure) intercropping. Intercropping green manure is an effective measure to fertilize and make full use of the soil of walnut orchard. Green manure crop is a kind of high quality fertilizer source because of its easy cultivation, high yield and good fertilizer efficiency. In the walnut orchard with poor site conditions, insufficient fertilizer sources and weak tree potential, green manure crops can be made in the garden every other year, and during flowering and budding stage, they can be buried in the soil through mid-tillage, so as to increase soil organic matter and improve the physical and chemical properties of soil. Green manure crops such as alfalfa, alfalfa and mung beans are suitable for intercropping in walnut orchards. Reasonable selection can be made according to the environmental characteristics of soil and the adaptability of green manure, such as Amorpha fruticosa has strong adaptability, all kinds of soil can grow, walnut orchards with better soil conditions are more productive, Astragalus adsurgens is barren and can be planted in sandy land. Sesbania and other orchards with salt-alkali tolerance, moisture preference and high groundwater level can also be planted. Perennial perennial root green manure crops can grow continuously for 3 ~ 4 years, cut 3-4 times a year, and the cut grass is buried on the tree plate or orchard to increase soil organic matter.

Strip or whole garden intercropping should be used in    intercropping. No matter which form is used, leave a tree disk with a diameter of more than 1 meter under the tree, and pay attention to crop rotation. With the expansion of the crown, the intercropping area decreased year by year. After 5-6 years of planting, the intercrop withdrew when the crown was basically closed. Crops should be loosened, weeded, fertilized and irrigated every year to prevent desolation or compete with trees for water and fertilizer.