Technical measures for recovery of production in forest special seedling and flower nursery after disaster
First, field seedlings
1. Shake off the ice and snow at the right time. Under the premise of ensuring personal safety, clean up the snow on the plant in time to avoid freezing damage; do not shake it down forcefully, lest fallen leaves and branches are broken, and protect the tree as much as possible.
2. Clear the ditch and drain the water. Do a good job of clearing ditches and drainage around the nursery in time, reduce the soil water content of the nursery, and prevent frost damage and waterlogging damage from happening at the same time. Seedlings suffering from severe freezing injury should pay more attention to the management of soil moisture after germination. Excessive waterlogging and drought are not conducive to the recovery of plant growth.
3. Support the binding bundle. Curved and lodging seedlings should be righted or replanted in time, and brackets should be tied up if necessary. Plastic sealing and heat preservation measures should be taken for the interface of the grafted seedlings in the aboveground part to prevent and reduce the freezing injury of the seedlings.
4. Wound care. The torn branch should be held back to the original growth position in time, tied and fixed on the crack with a thin brown rope, and then evenly coated with protective agent (protective agent can be used for carpentry white paint), and then wrapped with a film about 2 cm wide. The implementation of this measure should be timely, the split cortex should be closely matched, the loosening should be carried out after the firm healing, and the torn branches should be properly removed to reduce the consumption.
5. Pruning. Pruning is one of the commonly used remedial measures after freezing injury, which is treated separately according to the degree of plant damage: for the plants with mild freezing injury, we should strictly grasp the light pruning of "shallow rather than deep" to clean up the plants, so as to facilitate the germination of buds; for the severely damaged plants, deep pruning or heavy pruning should be carried out to cut off the frozen parts in time to promote the germination of new shoots.
6. Cultivate soil and fertilize. When there is no stagnant water in the nursery ditch, the soil should be cultivated in time to increase the ground temperature. the height of the soil should be 3cm higher than the ground according to the difference of seedling species and seedling age, and be removed when the soil temperature is higher than 10 ℃. Precious seedlings can be covered with rice straw, leaves, sawwood ash and so on to increase heat preservation. For lighter frozen plants, 0.2%-0.5% urea can be used for extra-root topdressing for 2 or 3 times. After thawing in early spring, sufficient spring fertilizer is applied early to restore growth. Plants with severe freezing injury should be fertilized with thin fertilizer and pay special attention to the period of fertilization for the purpose of promoting spring and summer shoots and controlling autumn shoots.
7. Pest control. Frozen seedlings grow weakly and tend to cause diseases and insect pests. The 800-fold solution of methyl topiramate and chlorothalonil can be used to spray disinfection, and Bordeaux solution can be used to brush the bark and wound to prevent the occurrence of diseases. Cultivate the soil in time to maintain the humidity of the trunk and make it recover naturally. In addition, it is also necessary to monitor regularly and take corresponding measures to control diseases and insect pests as soon as they are found.
2. protected cultivation of seedlings and flowers
1. The shed body is reinforced. For the damaged flower greenhouse, lose no time to repair and strengthen the greenhouse skeleton and greenhouse film, remove snow immediately, reduce the pressure on the greenhouse body, increase the light transmittance of the film body, and increase the greenhouse temperature.
2. Drainage and anti-freezing. Remove the snow in the shed and the ditches around it in time, clear the ditch and drain, so as to prevent the melting snow water from seeping into the shed through the soil at the foot of the shed.
3. Reasonable topdressing. The frozen plants were sprayed with quick-acting fertilizer to promote the recovery of plant growth and enhance the ability of cold resistance and freezing resistance. Rose, Cymbidium, Cymbidium and other flower seedlings should be applied different fertilizers according to different varieties.
4. The temperature in the shed is increased. Temporary heating measures such as light bulbs, heating and temporary combustibles are adopted to reasonably control the temperature in the shed and prevent the occurrence of gas damage in combustion. In order to increase the temperature and prevent freezing, the shed can be buckled in the greenhouse, arched with fine bamboo and covered with double-layer film.
5. Pruning to prevent disease. Branches and leaves that are seriously frozen should be cut off and cleared out of the shed in time to avoid mildew and disease. Timely spraying protective agents and insecticides and fungicides, but also combined with topdressing, strengthen management, and restore growth as soon as possible. After the growth of the plant was restored, broad-spectrum pesticides such as methyl topiramate were sprayed on the leaves to control the occurrence of the disease.