Prevention and Remediation Techniques for Fertilizer Damage

Fertilizer is the grain of crops. Reasonable fertilization can maintain and improve soil fertility, as well as increase crop yield and quality. However, fertilizer damage often occurs in agricultural production due to improper selection of fertilizer varieties and application methods. Recently, our station has received feedback from many farmers. According to our investigation, most of the garden plots affected by fertilizer this time have heavy sandy soil, shallow soil layers, and high concentration compound fertilizer or urea application, The application rate is 20-30 kg/mu, using strip or hole application, with a length of 40-50 cm and a depth of 5-10 cm. The application time was in mid to late December last year, and about a month after application, leaves appeared. Now, when the fertilization hole is dug, it can be seen that there is a "hemp root layer" under more fertilizers, and the roots have been rotten and peeled off. The main reason is that the application of fertilizer is concentrated and located in the active layer of root system. After application, the Osmotic pressure of local soil solution is too high, causing salt damage to the plant, waterlogging damage to the root system, causing damage to the ability of the root system to absorb water and fertilizer. Last year, when the soil was dry, it was dug for dry application. After application, there was a light rain month after month, aggravating the occurrence of fertilizer damage.

For those that have already suffered fertilizer damage, remedial measures should be taken by excavating the soil at the fertilization site, watering the soil in the hole with clean water, diluting the concentration of soil fertilizer solution, cutting off the rotten coarse roots, covering them with new soil, and pruning the upper dead branches.

To prevent fertilizer damage, it is necessary to achieve reasonable fertilization:

1. Reasonably select fertilizer varieties. The perennial Cash crop should mainly use soil miscellaneous fertilizer and Manure, and use chemical fertilizer and Manure together. Applying soil miscellaneous fertilizer and Manure can not only provide various nutrients, but also improve the soil, improve the buffer capacity of the soil, and reduce the occurrence of fertilizer disasters. Similarly, fertilizers, including chlorinated fertilizers, are prone to fertilizer damage. Currently, there are a wide variety of fertilizers on the market with varying quality, and farmers should pay special attention when selecting them.

2. Improve the fertilization method. The winter and spring base fertilizer should be applied in an open ditch along the outer edge of the tree crown, with a depth and width of 20-30 centimeters each. After application, it should be covered with soil. When applying fertilizer as topdressing, it should be watered with water or applied when the soil is moist after rain.

3. Control the amount of fertilizer, especially nitrogen fertilizer. For orange and pear trees with a general yield of 50 kilograms, the amount of urea applied per plant should not exceed 100 grams, and other nitrogen fertilizers should not exceed 250-300 grams. For tea gardens, the amount of urea applied per plant should not exceed 25 kilograms. For young and diseased fruit trees, it is recommended to apply a small amount of urea multiple times.