How to Take Emergency Protective Measures When a Navel Orange Orchard Suffers Freeze Damage

Reporter Yan Zhangwen reports: With the weather continuing cold and rainy, can navel orange trees withstand it? On the morning of January 28, the reporter conducted a telephone interview with Fang Yiwen, director of the Municipal Citrus Science Research Institute. Director Fang Yiwen, who was observing freeze damage on site, told the reporter that in parts of Ningdu, Yudu, Ganxian and other places in the north and central regions, some navel orange orchards at higher altitudes have already suffered freezing damage, with ice forming on the leaves; as temperatures drop, the freezing line will continue to advance toward the southern areas, posing a greater threat to navel orange trees. According to the weather forecast, the rain, snow and freezing weather will continue until the end of this month, and temperatures will continue to drop. There is no time to lose in doing a good job of protecting orchards against freezing, and Fang Yiwen urged the broad community of fruit growers to immediately implement the following emergency measures.

Remove ice in time: Gently tap the trunk and large branches with a wooden stick to shake off the ice blocks on the leaves, avoiding prolonged contact between ice blocks and leaves that causes freeze damage, reducing the pressure on the canopy and preventing large branches from breaking under the weight. Note that you must not directly strike small branches and leaves, and do not injure the main trunk by tapping. If heavy snow occurs later, this method can also be used. 2. Canopy covering: Cover the entire canopy with rice straw or weeds; for large mature trees, some shade netting used for weed control can be spread over the canopy for covering. 3. Tree disk covering: Cover the tree disk tightly with rice straw or weeds, with a weed thickness of more than 10 cm, and place some soil clods on top to prevent it from being scattered by the wind. The root collar area should also be covered and earthed up, leaving no gaps, to raise soil temperature. 4. Trunk wrapping with straw: Wrap the entire main trunk with rice straw, paying special attention to wrapping the root collar area tightly to prevent freeze injury to the main trunk.

After the rain passes and the sky clears and temperatures warm up again, recovery work after freezing should be carried out: promptly remove frozen leaves; shallow loosening of the soil and light fertilization to promote recovery of tree vigor; promptly spray chemicals to prevent and control citrus anthracnose; and prune moderately.