Three key points in Post-harvest Management of Walnut trees

Walnut trees consume a lot of nutrients due to the need of fruit during the fruiting period. therefore, walnut trees must be managed reasonably and effectively after fruit harvest, which can not only ensure the faster recovery of walnut trees, but also play an important role in preventing the occurrence of diseases and insect pests.

1. Dig deep into the soil after picking fruit. The roots of walnut trees generally go deep into the soil, and whether the soil has good air permeability is directly related to the growth of the root system. Therefore, after the fruit is harvested, the orchard soil should be deeply turned over. Deep turning is usually carried out before the fallen leaves of fruit trees, with a depth of 25cm to 40cm. At this time, it is also the second peak of walnut root growth, deep turning is conducive to root growth, many root injuries are easy to merge with new roots, and soil nutrients transform quickly, which is conducive to the accumulation of tree nutrients.

two。 adequate manuring. The fertilization period is from early September to late October. Fertilization can choose organic fertilizer and biological bacterial fertilizer suitable for the growth of walnut trees, which can improve soil, prevent consolidation, promote air permeability, and add appropriate amount of nitrogen, phosphorus, potassium and other medium and trace element fertilizers. For the walnut trees of the first fruit, 15 kg of high quality organic fertilizer, 0.15 kg of biological bacterial fertilizer, 1 kg of nitrogen, phosphorus and potassium fertilizer and 200 g / mu of Ciba boron and zinc trace element fertilizer were applied to walnut trees at full fruiting stage. 25 kg of high quality organic fertilizer, 0.25 kg of biological bacterial fertilizer, 2 kg of nitrogen, phosphorus and potassium fertilizer, and 300 g / mu of Ciba boron and zinc trace element fertilizer. When fertilizing, it is necessary to spread fertilizer under the crown for the first fruit trees of 2 ~ 4 years old, and for more than 5 years old trees, they can apply fertilizer in the ditch, mix the fertilizer and soil and fill it back into the ditch, or alternately open the ditch and turn the tree plate after spreading. In addition, to cooperate with watering, generally deep turning or ditching fertilization should be timely and fully irrigated, and the soil can be irrigated again in dry years before freezing.

3. Timely and correct pruning. Walnut trees must grasp the appropriate time when pruning, generally dormant pruning is easy to cause bleeding and weaken the tree potential, and even cause local branches to die, therefore, it is best to control the pruning time before falling leaves in autumn or after sprouting in spring. Pruning is the best during the period from the Autumn Equinox to Cold Dew, when pruning is beneficial to wound healing as soon as possible in the same year. If the pruning workload is large, it can also be pruned 30 days after falling leaves or 25 days before sprouting in winter, which can reduce the adverse effects of bleeding on the tree. In addition, on the basis of mastering the appropriate pruning time, the pruning method must also be appropriate. At the young stage of walnut trees, the nutrition is exuberant, the branches grow rapidly, and the crown expands year by year. At this time, pruning should pay attention to cultivate the trunk, keep the main branches, retain the auxiliary branches, cut the squeezed branches, overgrown branches, thin and weak branches in time, and leave more fruiting branches in the crown. Pruning is best combined with pulling branches. Dense tree planting is supplemented by pruning and pruning. This pruning can not only ensure the uniform distribution and symmetrical growth of the main branches, but also make the crown clear, transparent and unbiased, ensure the balanced development of the tree potential, and gradually cultivate into a full tree with large fruit volume.

Liu Chaobin