Walnut watering method
Under normal circumstances, walnut trees need about 600 ~ 800 mm annual precipitation to meet the needs of walnut tree growth and development. If the precipitation is insufficient or unevenly distributed, irrigation is needed.
Watering the walnut trees in early spring: Generally, in March-April, the walnut trees enter the germination stage and begin to sprout and branch. At this time, the spring drought and water shortage in the northern region affected the growth and development of walnut trees. Irrigation combined with fertilization can promote flowering and fruit setting during this period.
Watering the walnut tree at flowering stage: In May and June, after the female flower is fertilized, the fruit grows rapidly or the female flower bud begins to differentiate and form. This period needs a lot of water and nutrition. Irrigation should be carried out during drought.
Watering during the fruit development period of walnut trees: Generally, walnut trees are in July and August. During this period, nucleoli began to develop and flower bud differentiation reached a climax, which required sufficient water supply. At this time, the north has entered the rainy season and generally does not need irrigation. If there is long-term high temperature and drought, irrigation is needed.
Watering walnut trees in autumn: from the end of 10 to the beginning of 1 10, irrigation can be combined with base fertilizer in autumn, which is not only beneficial to soil moisture conservation, but also can improve the cold resistance of young branches. During the growth of walnut trees, long-term water accumulation on the surface or high groundwater level will affect the growth and development of walnut trees, leading to root suffocation and death. Therefore, it is necessary to reduce the groundwater level or eliminate surface water in time to provide a good environment for the growth of walnut trees.
Watering method of walnut seedlings
Generally speaking, watering should be based on the growth size of walnut seedlings, the spacing of walnut seedlings and the types of soil, such as sandy soil, cohesive soil, soil moisture and so on.
The most suitable irrigation amount for walnut seedlings should be 1 irrigation, which can make the soil moisture in the distribution range of walnut roots reach the most favorable level for growth and development. Generally, 1 m irrigation is appropriate. There are many ways to calculate the irrigation amount, and today we use a more common method.
According to the water holding capacity of different soils, that is, according to the soil water content before irrigation, soil bulk density and the required soil soaking depth, the irrigation amount in a certain area is calculated. Here is a formula: irrigation quantity = irrigation area? How deep is the soil soaked? Soil bulk density? (Field capacity-soil moisture before irrigation)
For example, if an 8-mu walnut orchard is irrigated, the soil moisture at the depth of 1m will reach the field capacity (28%), the soil bulk density will be 1.25, and the soil moisture in the root distribution layer will be 18% before irrigation. Calculate the irrigation amount according to the above formula =8? 667? 1? 1.25(0.28―0. 18)= 667m？ . Before irrigation, soil moisture should be measured before each irrigation. Field capacity, soil bulk density, soil immersion depth and other items can be measured 1 time every three years, and the data is more accurate.
Pruning technology of walnut
1. Pruning of young trees: according to the different growth and development characteristics of each variety, weak branches, cross branches, overlapping branches, parallel branches and diseased branches are mainly pruned to cultivate backbone branches and fruiting branches at all levels. The specific methods are: controlling secondary branching; Control long branches; Treating vigorous vegetative branches; Loosen the branches that are too dense and deal with the lower branches on the back.
2. Pruning of adult trees: the tree shape of walnut trees just entering adulthood is basically formed, and the output is gradually increasing. The main pruning tasks of walnut trees in this period are: continue to cultivate main branches and lateral branches, make full use of the early achievements of auxiliary branches, actively cultivate fruiting branches and expand the fruiting parts as much as possible. Its pruning principles are: removing the strong and retaining the weak, releasing first and then shrinking, and combining the releasing and shrinking to prevent the generated part from moving out.
3. Pruning of trees in full fruit stage: Most of the large walnut trees are close or closed in full fruit stage, and the peripheral branches gradually increase, and most of them become fruiting branches. Due to poor illumination, some branchlets dry up, and light bands appear on the back of the main branches, and the fruiting parts move outward, which is easy to bear fruit every other year. Therefore, the main tasks of pruning in this period are: adjusting the relationship between vegetative growth and reproductive growth, constantly improving the ventilation and light transmission conditions in the crown, and constantly updating the fruiting branches, so as to achieve the goal of high and stable yield.
4. Pruning of aging trees: Walnut trees enter the aging period, and the peripheral branches droop, resulting in a large number of? Focus tip? At the same time, a large number of long branches germinated and naturally regenerated, and the yield also decreased obviously. In order to prolong the fruiting period, it can be renewed and rejuvenated. The specific pruning methods are as follows: ① trunk renewal (big renewal): all the main branches are sawed off to make them grow branches again and form main branches. ② Regeneration (middle regeneration) of the main branch retracts at the proper position of the main branch to form new lateral branches. ③ collateral regeneration (small regeneration): Retract the primary collateral to a proper position to form a new secondary collateral. Its advantages are: the formation of COVID-19 and the rapid increase of output.
Walnut tree cultivation should pay attention to the following problems
Walnuts are widely distributed in China, starting from southern Liaoning in the north, reaching northern Fujian in the south, Shandong and Zhejiang in the east and Qinghai, Xinjiang and Sichuan in the west. It can grow normally at an altitude of 500m-2500m, and walnuts grow well at an altitude of 500m- 1000 m in our province.
Walnut likes light, fat and water, and its root system is developed. Therefore, when choosing a walnut orchard, we should choose a place with good soil fertility conditions, soil thickness above 1.5m, slope below 25 degrees, leeward and sunny, space circulation and sufficient sunshine.
The recommended density of walnut planting, the short branch variety with early fruit and early dwarfing is: 3.5 meters between plants? 5 meters or 4 meters? 6 meters, 38-28 plants per mu; The row spacing of late-maturing varieties is: 5 meters? 7 meters or 6 meters? 8 meters, per mu 19- 14 plants.
Problems and Solutions in Walnut Seedling Cultivation
There are many varieties of walnuts, each with its own characteristics. To cultivate excellent varieties, we must first understand the reproductive characteristics and advantages of walnuts, master the key points and techniques of grafting, actively cultivate excellent varieties, and enhance adaptability and pest resistance.
1, which solved the problems of walnut selection and increasing economic benefits.
Walnuts are mostly cross-pollinated, with mixed varieties and great differences in advantages and disadvantages. Grafting seedlings is the best way to obtain excellent varieties, make them stable and high-yield, bear early fruits and have strong resistance.
2. Really solve the problem of seedling purity.
Due to the implementation of the project of returning farmland to forests and the large-scale planting of walnuts, walnut seedlings are in short supply. Therefore, seedling grafting appeared? A knife? The phenomenon of false grafting and inferior variety grafting has caused extremely serious consequences, so we must strengthen our study, actively practice, strive to master the technology and improve the ability of seedling identification.
Several measures to be taken to develop walnut planting
1, it is necessary to strengthen popular science propaganda and let farmers fully understand the relevant knowledge of walnut seedling cultivation.
2. Improve the cultivation speed of excellent walnut seedlings and strengthen the comprehensive management after planting. With the expansion of high-quality walnut planting area, the supply of high-quality walnut scions will increase.
3. Popularize grafting technology, do a good job in grafting technology training, mobilize the masses to vigorously raise seedlings, improve the yield and quality of seedlings, reduce the price of grafted seedlings of improved varieties of walnuts as soon as possible, and increase the tolerance of farmers to develop walnuts.
4. Forestry administrative law enforcement departments should intensify the crackdown on fake and shoddy seedlings, severely crack down on illegal personnel who manufacture and sell fake seedlings, purify the seedling market, and let farmers who plant walnut seedlings really buy real high-quality walnut seedlings and reduce unnecessary losses. Only in this way can walnut, an ancient economic tree species, develop healthily in a scientific, orderly, reasonable and efficient direction.