Recently, the central and eastern parts of China have suffered the strongest rain and snow weather process this winter, which has brought adverse effects on the production of fruits and tea in local areas, especially the freezing rain has caused great damage to trees and protective facilities. The meteorological department expects widespread rain and snow to continue in the south, and the south will warm up significantly after Chinese New Year's Eve. In order to do a good job in coping with freezing rain and snow weather and restoring production after the disaster, the Planting Industry Management Department of the Ministry of Agriculture and Rural Affairs organized the National Agricultural Technology Extension Service Center, the Fruit Tree and Tea Expert Guidance Group of the Ministry of Agriculture and Rural Affairs, and the National Citrus and Tea Industry Technology System to study and formulate the "Technical Guidance on Fruit Tree Tea Coping with Continuous Rain and Snow Weather and Post-disaster Management".
1. Fruit trees. (1) Continue to respond to heavy rainfall and snow
1.Cover. It is recommended to cover the tree with film, non-woven fabrics, straw curtains and other insulation materials to reduce direct contact between the canopy and rain and snow.
2.Facility reinforcement. Strengthen protective facilities with weak support structures such as rain shelters and simple greenhouses, and increase the support density to prevent short-term heavy precipitation and snow from crushing the facility structure. For facilities with a high risk of collapse, priority should be given to protecting the skeleton structure of the greenhouse, and if necessary, the film or protective net should be cut in advance to reduce the load on the top.
3.Warm up at the right time. When the amount of short-term snowfall is large, under the premise of ensuring the safety of personnel, the snow bearing situation of the facility shall be inspected in time to remove excessive snow. In addition, fumigation measures can be taken according to the situation to strengthen the long-wave optical inverse radiation of the orchard, increase the temperature of the orchard, and reduce the impact of low temperature.
(2) Take timely recovery measures after rain and snow disasters
1.Snow removal and soil management. After heavy snow or frost, remove snow or frost from trees and under tree trays in a timely manner. Timely loosen the soil in the whole garden or tree tray (avoid hurting the roots), improve soil aeration, and promote new roots.
2.Tree managementIf the tree has been affected by freezing rain, it is not advisable to forcibly de-ice to prevent secondary mechanical damage and wound infection of the tree and branches and leaves. The wounds of the broken branches are cleaned and protected, and the broken or frostbitten branches are pruned, cleaned and harmless.
3.Trim in time. Remove the leaves that have been wilted or scorched as soon as possible, cut off the frozen shoots after the temperature rises in spring, and retain as much as possible the inside of the canopy and the lower branches. The large scissors (saws) should be smoothed and the wound should be protected with appropriate protective agents. For backbone branches that are directly exposed to strong sunlight, they should be painted white or tied with shade nets to protect from the sun.
4.Fertilizer and water management. After the temperature rises, in accordance with the principle of "diligent application and thin application", apply 2-3 times of high nitrogen and low potassium or other high-quality commercial water-soluble fertilizers in time. For frost-affected trees that have not fallen their leaves, use 01% urea and 03%—0.Foliar spraying of 5% potassium dihydrogen phosphate was carried out, and 2-3 sprays were applied continuously at intervals of 15-20 days.
5.Pest and disease control. After the frost pruning is completed, the dead branches and fallen leaves should be cleaned up in time for destruction. Thoroughly disinfect the whole park with stone sulfur mixture, sodium pineate or mineral oil + acaricide + fungicide + insecticide in time to prevent pests and diseases. In the process of new shoots extraction, spray pesticides in time to control pests and diseases and protect new shoots.
2. Tea. (1) Continue to deal with rain, snow and freezing weather
1.Set up wind barrier protection. For the low temperature weather accompanied by strong winds, wind barriers can be built at the north and west tuyeres of the tea garden, and the wind barrier materials are preferably straw curtains, and plastic films, multi-layer shade nets and other materials can also be used.
2.Strengthen the canopy to protect against cold. Before the cold wave comes, mature tea gardens can be covered with non-woven fabrics, woven bags, films or shade nets and other materials directly on the canopy of tea trees, or they can be covered with straw, crop straw, pine branches, etc. Be careful to remove the mulch as soon as the cold spell is over.
3.Do a good job of laying grass between the rows. According to local conditions, cover the tea row soil with straw, wheat straw, soybean straw, rape straw, green manure, wheat husk, bean husk, rapeseed husk, fallen leaves, bark, sawdust or wild grass, etc., and the thickness of the cover should generally reach more than 10cm, and it is advisable not to expose the soil.
4.Strengthen plant management. Tea processing factories should effectively establish a sense of safety, in case of rain and snow weather to strengthen inspections, especially the simple factory roof of the thick snow should be immediately organized to clear, when the snowstorm should be swept with the down, to prevent the collapse of the plant.
(2) Strengthen the management of tea gardens after the disaster
1.Remove snow from the canopy in a timely manner. Before the snow melts, remove the snow from the canopy in time to prevent the snow from crushing the production branches and sprouted branches or causing frost damage. Snow can be removed by blowing with a snow blower or by broomsticks, tapping on the side of a branch, etc., or when the temperature is above 0 degrees, the snow can be washed with sprinkler irrigation equipment.
2.Prune at the right time. After the temperature rises, for the tea trees that are severely frozen, the dead branches can be cut off at 1-2cm below the dead part to prepare for the germination of new shoots.
3.Fortified nutrients**. Tea trees harmed by ice and snow should strengthen soil nutrient management, should be applied early spring germination fertilizer, mature production tea gardens should apply 10-20 kg of 18-8-12 (N-P2O5-K2O) formula of tea tree special compound fertilizer per mu, young tea gardens per mu apply 5-10 kg of 15-15-15 (N-P2O5-K2O) formula of compound fertilizer, and can be combined with the application of foliar fertilizer. For tea plants with frozen roots, extra-root topdressing can be carried out after the leaves mature on the new branches. After the temperature rises, timely cultivation and weeding can improve the soil permeability and enhance the absorption vitality of the tea roots.