What to Do About Empty Chestnut Burrs? Causes and Control Methods Explained

Chestnut is a fruit we quite enjoy, but during cultivation, empty burrs can occur, causing a serious drop in chestnut yields and affecting growers' economic returns. The so-called empty burr phenomenon refers to that during the growth and development of chestnut, the spiny burr stops growing and forms a round ball shape, while the chestnut inside is shriveled, having only a shell and no kernel. So what causes empty burrs? How should they be prevented and controlled? Let's take a look.

1. Malnutrition

During the fruit swelling stage, chestnut needs a variety of nutrients. According to research, the content of reducing sugars, starch, amino acids and other trace elements in empty-burr chestnuts is much lower than in normally developing chestnuts, so malnutrition is also one of the causes of empty chestnut burrs.

Control methods: Soil is an important factor in chestnut growth. When planting, choose an area with relatively good soil fertility, and during cultivation strengthen fertilizer and water management, watering and fertilizing scientifically and reasonably to meet the nutrients needed for chestnut growth. When symptoms caused by malnutrition appear in the plants, apply additional fertilizer promptly to supplement nutrients. Before the fruiting stage of chestnut, appropriately apply some multi-element compound fertilizer to reduce the probability of empty burrs occurring.

2. Poor Pollination

Poor pollination of chestnut plants is also one of the main causes of empty burrs. Because chestnut is cross-pollinated, and the male and female flowers do not open at the same time, generally the male flowers open earlier and the female flowers later. Pollination is usually spread by wind, which limits the spreading distance, so the fertilization rate of the same plant is relatively low. In addition, if there is a long period of rainy weather during pollination, it can also lead to poor pollination.

Control methods: When planting, consider its cross-pollination characteristics. When establishing an orchard, several varieties can be chosen to pair with each other; these pollinate very well, improving the fruit-setting rate and reducing empty burrs. During the period when male flowers are open, appropriately prune and thin the flowers to reduce nutrient consumption, so the plant produces more female flowers. During pollination, manual assistance can be used, achieving a fertilization rate of over 95%.

3. Boron Deficiency

In practical production, it has been learned that boron is the most critical element for chestnut during the fertilization and fruiting period. A lack of it prevents chestnut from fertilizing normally, causing early abortion of the chestnut embryo and preventing the formation of normal nuts.

Control methods: During the fruiting period of chestnut, additional boron fertilizer can be applied to prevent this phenomenon, or borax can be mixed with water to make a solution for foliar spraying, once a week for 2-3 consecutive times, with excellent results.

4. Other Factors

In addition to the main causes of empty chestnut burrs above, there are also some reasons that can directly or indirectly lead to empty chestnut burrs, such as climate, variety and pests and diseases. When chestnut is planted under unsuitable climatic conditions, such as excessive rainfall, or temperatures that are too low or too high, empty burrs can occur. Some varieties inherently have weak fruiting ability and are very prone to empty burrs; as for pests and diseases, needless to say, this is an issue that cannot be ignored in chestnut cultivation, and in severe cases it not only causes empty burrs but also leads to the death of plants over a large area.

Control methods: Choose to plant in areas with a suitable climate, select varieties of excellent quality, and continuously graft and cultivate improved varieties during cultivation. Once inferior varieties are found, eliminate them promptly, strengthen pest and disease control work, and treat them promptly once discovered.

The above is all the content on the causes of empty chestnut burrs and the prevention and control methods. To learn more about chestnut cultivation, please stay tuned to us.