Study on biological characteristics of 1 walnut
Walnut is a tall deciduous tree with a height of 25m and a DBH1m. The trunk of the walnut tree is gray, and it will not crack in the young tree stage, but will crack longitudinally in the old tree stage. The leaves of walnut tree are odd pinnate compound leaves, which are alternate, among which the small leaves are opposite and the overall shape of the leaves is oval. There are two types of blades: smooth and serrated. The flowers of walnut trees are unisexual and monoecious. The fruit of walnut tree is oblate and spherical, with smooth exocarp, lignified endocarp, high hardness and wrinkles on the surface. Usually, the flowering period of walnut trees is April-May, and the walnut trees will enter the fruiting period in September-65438+10.
2 walnut planting techniques in Shishan area
2. 1 Reasonable garden selection
Because walnut trees like light and cool, and have strong drought resistance, they should choose to build gardens at an altitude of 500 ~ 1500 m in rocky mountainous areas. Try to be the middle and lower part of sunny slope or semi-sunny slope, and ensure that the slope does not exceed 25. In addition, the thickness of soil layer in the garden is required to be greater than 60cm and the pH value should be controlled in the range of 6.5 ~ 7.5. On this basis, the soil layer should be loose and have ideal air permeability.
2.2 Soil preparation technology
If it is the planting condition of fish scale pit, in the process of soil preparation, semi-circular pit should be excavated in the area with thick soil layer, and the topsoil and core soil should be piled up separately. At the outer edge of the pit, stones or core soil can be used to effectively form stalks to ensure that the pit is enclosed. The requirements for the stalks are to control the width at 30cm and the height at 50cm, and the stalks must be compacted firmly to resist the scouring and soaking by rain. Generally speaking, the horizontal length of the pit is 1 ~ 1.5m, and the vertical width is 0.6 ~1m. Fill the pit evenly with topsoil, litter and weeds, and ensure that the thickness of the living soil layer is about 50 cm. In addition, the pits should be arranged in zigzag, and the slope should be fish-scale. This integral technology is usually applied to steep slopes with a slope of not less than 25 degrees or mountainous areas with thin soil layers but more gravel.
If it is a horizontal belt planting condition, it is necessary to complete the excavation of the horizontal belt along the contour line, and pile the topsoil and core soil [Jishan Huayao] separately. It should be noted that the width of the horizontal belt should be controlled at around 1 ~ 1.5m, and the length is not limited, so as to ensure that the horizontal belt goes around the mountain and the belt spacing is 3 ~ 4m. Grass belts can be reserved between horizontal belts to achieve the purpose of slope protection and avoid soil erosion. This horizontal belt soil preparation technology is generally used in rocky mountainous areas with gentle slope and thick soil layer.
2.3 Selection of planting varieties
Walnut varieties directly determine the time and quality of fruiting. At present, many scientific research institutions have cultivated high-quality walnut varieties in scientific research. Only by grafting cultivation can the effect of variety characteristics be ideal. On the whole, Jinlong strain and Lin Zhong strain can be the first choice for walnut planting.
2.4 Seedling selection and planting
In the process of walnut planting in Shishan area, the strong seedlings grafted for 2 ~ 3 years are selected, and the high-yield period can be reached after 4 ~ 5 years by dwarf and close planting. Because walnuts are monoecious flowers, cross-pollination is usually used. In this case, 2 ~ 3 walnut varieties should be selected for configuration and cultivation in walnut orchard. In rocky mountainous areas, it is required to control the spacing between walnut plants, and the specifications of planting holes are 50kg of farm manure and calcium superphosphate 1kg for each customized hole. Usually, the best effect is to colonize between September ~165438+10 or before germination. After the planting work is completed, it is necessary to irrigate the root water in time and cover the surface of the tree tray with weeds to effectively improve the survival rate. Finally, it is necessary to ensure that seedlings are fixed in time to avoid drought death.
Analysis of walnut management and protection technology in Shishan area
3. 1 soil management measures
3. 1. 1 farming management
In order to ensure the early fruiting of young walnut trees and achieve the purpose of planting large stems and high yield, deep ploughing and green pressing or organic fertilizer pressing can be used in walnut orchard. Spring, summer and autumn can be deeply ploughed. If spring is selected, it should be carried out before germination; If you choose summer or autumn, it should be done after the rain, with fertilization to ensure that weeds are buried in the soil. In the intertillage operation, deep ploughing should be carried out gradually at the planting hole position, and the depth should be controlled between 20 and 60 cm as far as possible, so as not to cause serious damage to thick roots with a diameter exceeding 1cm.
3. 1.2 Fertilization management
Nitrogen and potassium are always indispensable elements in the process of walnut planting in Shishan area. Wherein the nitrogen content obviously exceeds the potassium content. Therefore, appropriately increasing the amount of nitrogen fertilizer can lay a solid foundation for improving the yield and quality of walnut planting. If the soil in rocky mountain area is short of phosphorus or calcium, it should be supplemented in time and the application amount of organic fertilizer should be increased appropriately. In the fertilization of young walnut trees, the basic principles of thin application and diligent application should be strictly followed. Topdressing can be carried out from the year of planting to after germination, once a month, and base fertilizer can be applied at the end of September. In the second, third and fourth years of walnut planting, fertilization is carried out in March, June, August and 10 every year. If it is an adult tree, it needs to apply base fertilizer once a year and topdressing twice. Among them, the base fertilizer should be applied in combination with deep ploughing and green pressing after fruit picking in autumn.
5,000 kg of organic fertilizer, 50 kg of phosphate fertilizer, 0/5 kg of urea/kloc, and 0/00 kg of plant ash/kloc were applied per mu. The number of topdressing is twice. The first time is before germination, applying 20kg urea and 0/500 kg water per mu. The second topdressing time should be between June and July to ensure the effective differentiation of flower buds and the continuous increase of fruit weight.
3. 1.3 Irrigation management
Because walnut trees like to be wet, if the soil is dry and short of water during growth, it will directly affect the success rate of fruit setting, resulting in thick pericarp mating and chronic nut development. In this case, appropriate irrigation should be carried out at flowering and fruiting stages, after fertilization and in winter drought.
3.2 plastic pruning measures
3.2. 1 Stage pruning of young trees
When the height of walnut seedlings reaches 80cm, coring can be carried out. After the young trees germinate, three buds with a distance of about 6 ~ 8 cm in different directions should be selected for seed retention. Cultivate it into a main branch. At the same time, all other buds within 5 ~ 6 cm around the three main branches should be erased to avoid adverse effects on the growth of the main branches. For buds that will not affect the growth of main branches, they can be picked when they grow to 20 ~ 25 cm. After branching, the buds in front are selected as extended branches, and another bud is selected as a side branch for cultivation. When the length of the lateral branch is 30cm, coring can be performed, and when the length of the extended branch is 45-50cm, coring can be performed. During the piling process, the pulling rope is selected to ensure that the distribution direction of main branches is even, and the angles of all branches are controlled at 45. Buds that do not affect the growth of extension branches and lateral branches should be smoothed or left according to the density. In general, the distance should be 15 ~ 20~25cm, leaving a bud. When its length reaches 20 ~ 25 cm, it should be cored and determined as an auxiliary branch.
3.2.2 Shaping and pruning in the result stage
The growth of walnut trees has entered the fruiting period, and the crown has been expanding, and the fruiting parts have increased obviously. In this way, the contradiction between growth and results will become more and more intense. At this time, the main goal of pruning work is to ensure the steady increase of walnut yield. In the process of pruning, we should pay attention to the effective cultivation of branches, and deal with drooping branches and back branches in time by rational use of auxiliary branches and long branches. In the early stage of fruiting, the fruiting branches must be cultivated in a planned way to increase the fruiting parts accordingly. In addition, the cavity in the crown cavity should be avoided as much as possible to avoid the outward migration of the resulting part. After walnut trees enter the full fruit stage, attention should be paid to the cultivation of branches. In the process of cultivation, we should always follow the pruning principle of putting first and then shrinking. Generally speaking, the long branches of walnut should not be left in the early stage of fruiting, so as not to have a negative impact on the tree shape, but they can be transformed into branches in the fruiting period.
The above is the management technology of walnut planting in Shishan area, which is organized by Huinong. com。 Have you learned?