Yining County has extensively cultivated jujube trees, but the region often faces heavy snowfall in winter. When the snow melts in spring, the area just below the snow line—approximately 20 cm above the ground—is exposed to melting snow, wind, and moisture, leading to decay of the trunk’s bark. This damage disrupts the tree's vascular system, causing it to dry out and die, resulting in significant losses for fruit growers. Many farmers are hesitant to expand their jujube plantations due to concerns about bark cracking and sap leakage. In recent years, during the establishment of new jujube orchards, a method involving wrapping the young trunks with plastic film has been adopted, and the results have been very promising.
First, let's explore the reasons behind this issue:
1. **Climate Factors**: Yining County enjoys favorable climatic conditions, with an annual accumulated temperature of over 3400°C above 10°C, 2800 hours of sunshine per year, and annual rainfall not exceeding 600 mm. The frost-free period lasts about 168 days, and the maximum snow depth can reach around 27 cm in January.
2. **Variety Factors**: The main jujube varieties grown in the county are Zanhuang Dazao and Lizao. After comparing these varieties, it was found that both suffer similar levels of damage from the winter snow.
3. **Topography and Soil Factors**: Observations show that jujube orchards located on higher ground with good air circulation and sunlight tend to have faster snow melting in spring, preventing ice formation and reducing the risk of trunk splitting. In contrast, low-lying, moist, and windy areas experience frequent trunk cracking at about 20 cm below the snow line. This leads to the death of trees due to the blockage of their conducting tissues. Each spring, farmers have to prune and retrain the branches, which delays flowering and fruiting. In some cases, the fruits fail to mature, greatly affecting the income of local fruit growers.
Second, here are the measures taken to address the problem:
1. **Strengthen Field Management**: Regular pruning and cultivation help develop strong, healthy trees. In autumn, it's important to apply pesticides to the ground and trunks to prevent pests like fly dust from laying eggs and damaging the bark.
2. **Use of Plastic Film Wrapping**: Before winter snowfall, wrap the young trunks with plastic film (cut into 3 cm wide, 1-meter-long strips) at a height of 25–30 cm above the ground. Ensure it is tightly wrapped to prevent the bark from being soaked when the snow melts. When the snow melts in spring, remove the film and spray a fungicide. This method is applied continuously for two years during the early growth stage. Once the tree reaches three years old, its bark becomes thicker and more resilient, no longer requiring this protection.
3. **Summary**: Before establishing large-scale jujube orchards, we tried using flax or cloth strips to wrap the trunks, but the results were unsatisfactory. Burying soil around the base sometimes caused branch breakage, leading to further damage. Since the introduction of the plastic film wrapping technique in 2002, the development of jujube orchards has significantly improved, with better survival rates and higher yields.
Notebook Ultrasound Scanner,B W Ultrasound Machine,Ultrasound Bone Densitometer,Ultrasound Machine Instrument
Mianyang United Ultrasound Electronics Co., Ltd , https://www.uniultrasonic.com