Key points of management of ginkgo trees in autumn

Ginkgo biloba (Ginkgo biloba L.) is a deciduous tree of Ginkgo biloba family. Ginkgo biloba, which appeared hundreds of millions of years ago, is the oldest relict of gymnosperms left over from the Quaternary glacier movement. Ginkgo biloba is rare and scattered in the world, hundreds of years old trees are rare, and all other plants of the same class have become extinct, so ginkgo biloba is also known as a living fossil. Varieties and varieties are: yellow leaf ginkgo, tower ginkgo biloba, split ginkgo biloba, weeping branch ginkgo biloba, ginkgo leaf ginkgo and so on 26 kinds.

Growth habits of Ginkgo biloba

Ginkgo biloba is a rare Mesozoic relic tree species, which is endemic to China. Only wild trees are found in Tianmu Mountain, Zhejiang Province. Ginkgo biloba is born in the natural forest with an altitude of 500-1000 meters, acidic yellow soil (pH value 55.5) and good drainage, and often grows vigorously with coniferous and broad-leaved species such as Cryptomeria fortunei, Torreya trees and blue fruit trees.

Ginkgo biloba is a positive tree, which likes the deep loam with proper moisture and good drainage, and is suitable for growing in the subtropical monsoon area with superior hydrothermal conditions. It can grow well in acidic soil (pH4.5) and calcareous soil (pH8.0), while neutral or slightly acidic soil is the most suitable, the land that is not resistant to stagnant water is more resistant to drought, and grows poorly in too dry places, stony slopes or low wet land. In the initial stage, the growth is slow and the tillering is strong. The female tree generally begins to bear fruit in about 20 years, and the 500-year-old tree can still bear fruit normally. Generally, they germinate and spread leaves from late March to early April, bloom from early to mid-April, mature seeds from late September to early October, and defoliate from late October to November.

Key points of Management of Ginkgo biloba in Autumn

Autumn is the nutrient storage period of ginkgo trees. the key to the management of ginkgo trees in autumn is to maintain the assimilation function of leaves, prevent early defoliation, improve the cold resistance of ginkgo trees, promote root growth and accelerate flower bud differentiation. 1. Soil, fertilizer and water management. Applying base fertilizer in autumn. Before and after the Autumn Equinox, tree fertilization was carried out before and after production, that is, the amount of fertilizer was determined according to tree age, tree potential, fruit number, soil condition, etc., but generally 1 kg fruit was fertilized 1 kg to 2 kg, mainly mature organic fertilizer, and the fertilization depth was generally 40 cm to 60 cm. Semi-circular ditch or radial ditch was used to alternately open ditches to fertilize around the crown. Spray fertilizer on the leaves. For ginkgo trees that grow weakly or enter the full fruit stage, 0.2-0.4% urea and 0.3% potassium dihydrogen phosphate can be sprayed once a month after fruit harvest. Irrigation and drainage. Autumn is the late stage of vegetative growth. Reasonable irrigation is beneficial to the production and accumulation of nutrition and the formation of flower buds. At the same time, attention should be paid to drainage to prevent ginkgo trees from being infected by waterlogging. Deep ploughing and expansion of tree plates. Autumn ploughing is from August to November, and the soil is carried out before freezing, with a depth of about 20 cm. Deep turning can be carried out on a single plant, digging a circular trench on the vertical ground at the edge of the crown, or digging a trench between rows with a depth of about 60 cm. Do not cut off the thick roots of the expanded tree plate, and pile the topsoil and subsoil separately. When backfilling, the topsoil is mixed with rotten leaves, weeds, withered stems or other farm manure and put into the lower half of the ditch, and the original subsoil is placed in the upper half of the ditch, which can expand the tree disk according to the extension of the root system of ginkgo trees. Second, after shaping and pruning ginkgo trees, pull the corners of the strong branches to ease the tree potential and promote the formation of flowers; two coring of the new shoots are carried out to promote the branches and cultivate the branch group; the fruiting branches that are significantly weak and drooping after fruiting should be retracted properly; measures such as coring and twisting should be taken to control the vegetative growth of the overgrown branches sprouting in the crown, and the ungrown branches with no room for growth should be removed in time. For over-growing apricot orchards, paclobutrazol or PBO can be sprayed to control the tree potential to facilitate the formation of flower buds. Third, disease and pest control ginkgo trees are often harmed by diseases and insect pests after fruit picking. Timely spraying should be done according to the actual situation in order to protect leaves and increase tree nutrition accumulation. It can be sprayed to control aphids with 100-fold solution, and the red spider can be sprayed with 40% diclofenac EC 1500-2000 times or 1000 times. Spraying 800-1000 times of permethrin and trimethoprim to control Dendrolimus punctatus and Caterpillar navicular.