Key Cultivation Management and Pest and Disease Control Points for Horse Chestnut in the Longnan Mountain Area of Hui County

  Horse chestnut can also be called "suoluo tree," "tianshi chestnut," "kaixin guo," and "monkey chestnut." Its flowering period is from April to May, and its fruiting period is in October. Horse chestnut can be used for ornamental purposes and can also be made into various utensils. Moreover, the seeds can be eaten directly or used medicinally, and after the seeds are pressed for oil, the oil can also be made into soap. In short, it has many uses. Therefore, today the editor will discuss the cultivation management and pest and disease control measures for horse chestnut, one of the world's famous ornamental tree species.

  1 Growth Habits

  Horse chestnut likes light and is slightly tolerant of shade, but fears direct scorching sun; it likes a warm and humid climate and is relatively cold-tolerant; it has a deep root system and a long lifespan, and its sprouting ability is not strong.

  2 Planting Techniques

  Horse chestnut has a deep main root and few lateral roots, so it is a tree species that does not tolerate transplanting. The best time for planting is in early spring or late autumn. To improve its survival rate, the planting pit should be dug larger before planting, as this is beneficial to plant growth. When planting, it should not be too deep, otherwise it is easy to cause the plant to have suffocated buds. After planting, the backfill depth can be slightly 3-5 cm higher than the upper surface of the root ball.

  3 Irrigation

  After planting, water thoroughly immediately. Water a second time 7 days after planting, and a third time after another 10 days. After that, water according to soil moisture conditions. July-August is a period of abundant rainfall, so watering can be reduced or omitted. In September-October, water thoroughly once each month. At the end of November or in December, water thoroughly once with enough freezing water. In March of the second year, water thoroughly once with enough thawing water. April-May is a dry spring period, so the watering frequency can be increased, and freezing water should be watered well in late autumn. In the third year, water according to the method used in the second year. It should be noted that in dry seasons, water should be replenished in time, as this helps the crown become full and the branches become thick and strong.

  4 Fertilization

  Horse chestnut likes fertilizer, so sufficient base fertilizer should be applied before planting. The base fertilizer is preferably farmyard manure such as cow and horse manure and decomposed leaf fertilizer. In addition to applying base fertilizer at planting, fertilizer should also be applied throughout the entire growth period. In June of the year before planting, apply urea once to promote branch and leaf growth and increase the nutritional area. In August, apply a phosphorus-potassium fertilizer once to increase the degree of lignification of the plant's new branches. In late autumn, in combination with watering freezing water, apply some semi-decomposed fermented leaf fertilizer. In April of the second spring, apply urea once as a top dressing. In mid-August, apply a phosphorus-potassium fertilizer once as a top dressing. In late autumn, apply farmyard manure once according to the method used the previous year. This is beneficial for accelerating plant growth and helping the plant overwinter safely.

  5 Shaping and Pruning

  Shaping and pruning are carried out after leaf fall in winter each year or before bud break the following spring. Shaping and pruning are mainly based on the principles of maintaining a beautiful crown and good ventilation and light transmission, removing excessively dense branches, dead branches, pest- and disease-damaged branches, inner-canopy branches, slender branches, and poorly growing branches, so that the branches are evenly distributed and grow robustly, forming a good crown.

  6 Pest and Disease Control

  Common pests and diseases include scale insects, mulberry longhorn beetles, and root rot. For scale insects, 40% omethoate 1000-fold solution can be sprayed once every 5-7 days, for a total of 2-3 sprays; for mulberry longhorn beetles, adults can be captured manually, larvae can be removed with a hook, or 8% cypermethrin microcapsule formulation 100-fold solution can be sprayed for control; root rot is mainly caused by water accumulation in the tree pit, so drainage should be cleared in time in daily management.

Horse Chestnut Pests and Diseases and Control Methods

Main Diseases of Horse Chestnut

Disease Types

Horse chestnut is mainly harmed by leaf spot disease, powdery mildew, anthracnose, and sunscald, and can be sprayed with 70% thiophanate-methyl wettable powder 1000-fold solution.

Control Methods

Leaf spot disease, powdery mildew, and anthracnose can be sprayed with 70% thiophanate-methyl wettable powder 1000-fold solution. For sunscald, the trunk can be whitewashed in late autumn or early summer. The whitewash formula is: first dissolve 10 parts quicklime and 2 parts salt with a small amount of water, then add 1 part sulfur powder and 0.2 parts washing powder and mix well, then add 40 parts water and stir evenly.

Sunscald: It occurs on the trunk in summer. Whitewashing the trunk in late autumn or early summer can prevent sunscald. Dry grass or rice straw can also be used to cover the base of the trunk, and both methods can prevent the occurrence of sunscald.

Main Pests of Horse Chestnut

Pest Types

Pests include scale insects, caterpillars, and scarab beetles, and can be killed by spraying 50% phoxim emulsifiable concentrate 1000-fold solution.

Control Methods

Nettle caterpillars: The larvae feed on leaves. In the early stage of pest occurrence, timely spraying of 90% trichlorfon 800-1000-fold solution or 15% deltamethrin 4000-5000-fold solution can achieve good control results.

Control Methods for Horse Chestnut Pests and Diseases

  Horse chestnut (scientific name: Aesculus chinensis Bunge): It is a deciduous tree, up to 25 m tall, with bark dark brown or grayish brown, branchlets cylindrical, yellow-brown or gray-brown, with pale yellow lenticels. Winter buds are large and resinous. Palmately compound leaves, composed of 5-7 leaflets, dark green above, hairless, and below hairless except for sparse pubescence on the midrib and the base of lateral veins when young. The inflorescence is cylindrical, the inflorescence rachis is slightly pubescent, and the small inflorescences are usually composed of 5-10 flowers, spreading horizontally and obliquely, slightly pubescent. Flowers are polygamous, male flowers and bisexual flowers on the same plant, calyx tubular-campanulate, petals 4, white, oblong-obovate to oblong-oblanceolate. Fruit spherical or obovoid, yellow-brown, without spines, with very dense spots. Seeds usually 1-2 develop, nearly spherical, chestnut brown; hilum white, accounting for about 1/2 of the seed volume. Flowering period April-May, fruiting period October.

  Horse chestnut seeds are edible, but eating them directly tastes bitter and astringent. They must be boiled in alkaline water before they can be eaten, and they taste like chestnuts. Starch can also be extracted. The wood is fine and dense and can be used to make various utensils. The seeds can be used medicinally, and the oil pressed from them can be used to make soap. The horse chestnut has a beautiful tree shape, large and elegant flowers, and peculiar fruit shape. It is a rare tree species for viewing leaves, flowers, and fruits, and is one of the world's famous ornamental tree species.