1. Intercropping, cultivating, weeding and plowing Ginkgo afforestation has large gaps between the above-ground plants and rows. In order to promote the growth of young forests and prevent weeds and seedlings from competing for water and nutrients, forestlands with fertile soil can be interplanted with crops and Medicinal materials; forest land with poor soil is interplanted with green manure. After the canopy is closed, weeds will still breed. Cultivating and weeding should be carried out once a month from April to July every year. In order to mature the soil in the ginkgo afforestation land, the trench should be expanded after the autumn of the year of planting. The whole garden should be completed in 2 to 3 years. The root system should be damaged as little as possible during deep plowing. The topsoil and subsoil should be stacked separately. When backfilling, topsoil and organic fertilizer should be added. , litter, weeds, etc. are placed on the bottom layer, and the original subsoil is placed on the upper layer. After backfilling, it should be layered firmly, and if possible, it can be filled with water once to increase soil moisture. From now on, the soil will be plowed deeply every 3 to 4 years.

2. Top dressing: According to the nutrient needs of ginkgo at each stage of annual growth and development, in addition to applying sufficient base fertilizer when planting, top dressing is also required 4 times a year: the first time in early March before germination (in the south) ) to late March (in the north), when new roots are in the early stages of growth and approaching the budding stage, the tree is in urgent need of a large amount of nutrients. Nitrogen fertilizer should be the main fertilizer, with appropriate combinations of phosphorus and potassium fertilizers to promote vegetative growth and increase the fruit setting rate. According to soil fertility and tree size, apply 500 to 600 grams of urea, 300 to 400 grams of superphosphate, and 200 to 300 grams of potassium chloride per plant; the second time is from late April (in the south) to early May after flowering. (North) At this time, the seeds are in the young stage, the growth of new shoots is accelerated, and the nutrient consumption is very large, requiring a large amount of nutritional supplements; the third time is in July when the seeds are in the hard-core stage (early July in the south, mid-July and mid-July in the north) Late), which is a critical period for improving seed quality and yield and promoting flower bud differentiation, root growth and leaf photosynthesis. The above-mentioned two growth stages of post-flowering and hard-core stages urgently need complete nitrogen, phosphorus and potassium fertilizers. Each plant needs to input 400 to 500 grams of urea, 300 to 400 grams of superphosphate, and 250 to 350 grams of potassium chloride; the fourth time is at 11 After the leaves fall, apply 60 to 80 kilograms of decomposed manure or soil fertilizer and 400 to 500 grams of superphosphate to each plant. This fertilization can increase the stored nutrients in the tree and promote the early growth of the tree in the following year to accumulate nutrients. Fertilization methods are carried out according to conventional operations.

3. Irrigation and drainage Ginkgo needs a lot of water during the germination, branching, flowering and seed-setting stages. Watering should be done in time to meet the needs of its growth and development. Ginkgo is a tree species that likes moisture and is afraid of waterlogging. The soil moisture should not be too much. Too much water will cause leaf fall and root rot, and even the whole plant will die. Therefore, ginkgo orchards must do a good job in drainage, especially in gardens with high groundwater levels during rainy seasons. Pay attention to clearing ditches and draining water to avoid accumulation of water, so as to create good conditions for their healthy growth. On slopes, especially in mountainous areas, it is difficult to water and irrigate. The method of covering with grass and no-tillage can be used to conserve moisture and resist drought, that is, plow the ground deeply before planting, and spread grass evenly over the garden after planting, and cover it all year round without tillage. , the grass covering thickness is 15-20 cm, and about 2,000 kilograms of grass (straw, mugwort stalks and other weeds, etc.) are required for every 667 square meters. After covering the grass, a small amount of fine soil should be sprinkled on the grass to prevent fire and wind blowing away. Production practice has proved that the effect is very good. It can not only maintain soil moisture and reduce weed breeding, but also promote good plant growth and development. Therefore, the no-till method of grass mulching is worthy of promotion.

4. Timely prune and thin out temporary ginkgo trees with short canopy and dense planting according to the above medium density. The canopy will be basically closed in about 10 years. In order to achieve high yield, you should start to shrink the temporary plants at this time. Pruning is first carried out between the plant spacing in the row, and the branches that cross the permanent plants on both sides are cut back, while the top branches are retained to continue seeding. After 3 to 4 years of pruning, if the temporary plants are only a few short piles, they should be cut down. Later, when the canopy between rows is closed, use the same method of first pruning within the row and then cutting down the temporary plants between the plants to remove the temporary plants (temporary rows) in the entire row to create space for the expansion of the canopy of adjacent permanent plants between the rows. condition. In this way, the more than 20 ginkgo trees preserved per 667 square meters can, under normal circumstances, no longer be thinned out in the future.

5. Artificial pollination Ginkgo is a dioecious tree species, so pollination and fertilization are difficult. Therefore, before planting, the cultivation layout should be designed to facilitate the spread of pollen, and male plants should be evenly distributed at a ratio of 5%. However, due to various reasons in production, female flowers cannot be pollinated or are not pollinated enough. Especially during the flowering period, strong wind, rain, fog and other weather conditions bring certain difficulties to pollination. Artificial pollination can not only make up for the shortage of pollen, but also overcome disastrous weather, extend the pollination time, improve the quality of pollination, and ensure stable and high yield of seeds. According to a three-year experiment on low-yielding ginkgo trees at the Matou Forestry Station in Tancheng County, Shandong Province, artificial pollination increased the yield by 1.5 times compared to the control tree.

6. Adjustment of the size of the seed-bearing year of ginkgo. The phenomenon of the size of the ginkgo seed-bearing year is relatively common. This is mainly caused by poor management. The following methods can be used to adjust it.

(1) Strengthen fertilizer and water management. Seed trees consume a lot of nutrients. In order to make the roots deep and leafy, and the tree body strong, fertilizer and water management should be strengthened to avoid the phenomenon of large and small seeds. Increase fertilizer and water management, mainly apply flower-promoting fertilizer once before flowering, and apply seed-growing fertilizer once during the seed-bearing period. If the amount of seed is large, a reseeding fertilizer should be applied after harvesting. Top dressing should be mainly based on human and animal manure and phosphorus and potassium fertilizers. In addition, timely cultivating and weeding, timely watering, and drainage during the rainy season are required to ensure healthy growth of the trees.

(2) Proper pruning. Ginkgo seeds are planted on short branches. Therefore, the strength, number and age of the short branches are all important factors in the number of seeds.

The short branches should be strong and thick, with a thickness of more than 0.5 cm. Generally, short branches between 3 and 25 years old can produce seeds, but short branches between 5 and 15 years old have the strongest ability to produce seeds. Generally, each short branch can only bear 1 to 3 seeds. A middle-aged ginkgo tree often has tens of thousands of short branches. Under normal circumstances, only 1/5 to 1/3 of the short branches can bear seeds. For this reason, it is necessary to adjust the pruning. When planting in the new year, there are many seed-bearing branches and few vegetative branches. Winter pruning is generally done lightly, and only dry, densely grown, aging, diseased and insect-infested branches are cut off. More vegetative branches should be retained to ensure a certain amount of flowers the following year. . When there are a lot of flowers and the tree is weak, summer pruning can be used to remove some dense and weak branches to promote new shoots. When planting seeds in a young year, the vegetative growth is vigorous and the tree body accumulates more nutrients. On the premise of enriching the flower buds for the next year, the winter pruning should be appropriately heavier, thinning and shrinking, in order to control the number of flowers in the next year and balance the tree vigor. There will be a batch of short branches that will produce seeds that year, and a batch of short branches that will form flower buds that will produce seeds the following year. In this way, the phenomenon of over-annual seeding can be avoided.

(3) Ginkgo with sparse planting and fixed yield naturally has a high seed setting rate. Although the number of flower buds is adjusted through pruning, the number of seeds will still exceed the capacity of the tree. Too much flowering and planting, and overloading every year, not only reduce the quality of seeds, low commercial value, but also low yield, and lead to rapid weakening of tree vigor, greatly reducing and shortening the high-yield years and economic life, which requires thinning of seeds. For regular production, the middle and lower branches in the inner chamber should have sufficient nutritional storage, a high seed setting rate, and good seed quality. It is advisable to sparse less and leave more. The outer upper branches should sparse less and leave less, sparse less when they are prosperous, and leave more for weak trees. Generally, the seed thinning amount can reach 30% to 40%. The earlier the seed thinning time is, the better. It is usually carried out in mid-to-late May when the ginkgo is about the size of a soybean grain. Young trees with short crowns and dense planting can be combined with summer pruning and thinning. During the peak seeding period, use a small sickle tied to a bamboo pole to cut off overly dense seeds, or gently shake the branches to shake them off.

7. Control of seed drop. Ginkgo seeds often drop during the growth and development period of their seeds. In severe cases, a large number of seeds often drop within a few days, affecting the yield of the year. The main reasons for seed drop are: some are caused by dry climate or wind and rain that hinder the pollination of ginkgo, resulting in seed drop; some are caused by insufficient or imbalanced tree nutrients, disease, insect damage or other undesirable factors; some are caused by seed drop; Caused by excessive groundwater level or stagnant water, root rot, improper farming, root injury, etc. To control ginkgo seed loss, we must first analyze the reasons based on local conditions, and then start by enhancing tree vigor to maintain appropriate seed production, such as rational fertilization, strengthening soil management, lowering groundwater levels, timely drought resistance and drainage, moderate pruning, and improving pollination conditions. , maintain appropriate load capacity and prevent and control pests and diseases, etc. Only by strengthening comprehensive management can we ensure that ginkgo seeds rarely drop or do not drop during the growth period, which is an important part of improving ginkgo yield and quality.

8. Plastic pruning

(1) Plastic pruning of young trees. Ginkgo is a tall tree, and its dwarfed and densely planted tree shape is better to have a natural open shape. After the seedlings are transplanted and grafted, they will be dried and shaped in the winter of that year. The fixed stem height is 0.7 meters. It should not be too high or too low. If it is too low, the main branches will droop due to seeding, which will affect fertilization, cultivating, seed collection and other operations; if it is too high, the crown formation will be slow, three-dimensional seeding will be reduced, and the tree body utilization will be low. High, delayed seeding years. After setting the stem, select three directions on it. The strong branches with good angles are cultivated as the main branches, and the remaining branches are allowed to grow to accumulate nutrients and supply the growth of the tree. When the growth of the main branches is affected, they are gradually removed; In the second year, on the remaining main branch, select the buds on the anticlinal side about 60 cm away from the main trunk to make short cuts to promote the growth of side branches; in the third year, select the second main branch according to the method of selecting the first main branch, and the first Top the main branches in summer and autumn to continue to expand the crown, and pay attention to cultivating second side branches; cultivate the third main branch in the fourth year. After 3 to 4 years of shaping and pruning, the skeleton of the tree crown is basically formed. The main branches are inserted up and down to grow, the distance between layers is more than 60 cm, and the tree height is controlled at about 2.5 meters. In the future, pruning will be done to ease the tree vigor, and branch groups at all levels will continue to be cultivated to enrich the inner and outer parts and create conditions for entering the blooming period.

(2) Pruning during the peak planting period. The peak planting period of Ginkgo lasts for two to three hundred years. During this period, due to the large number of seeds produced year after year, it is easy to weaken, resulting in a decrease in yield. Therefore, in addition to strengthening soil, fertilizer, and water management, pruning should also be used to control the density of tree crown branches and leaves, maintain good ventilation and light transmission conditions, rejuvenate the tree vigor, replenish and renew the seed-bearing base branches, expand the seed-bearing area, and extend The number of years during the prime planting period will ultimately achieve the purpose of maintaining higher yields. In pruning, a combination of thinning and short cutting is adopted, with the principle of sparseness as the main focus, sparseness and density as sparseness, and thinning and thinning as the strong ones. The degree of pruning should be light, as heavy pruning will be counterproductive.

(3) Pruning of senescent trees The senescent trees mentioned here refer to old trees in their prime planting period, and also refer to trees that are young but have significantly weakened in growth. This is caused by poor management or too many seeds, overloading the tree, as well as damage by diseases, insect pests, humans and animals. Excessive pruning can also cause the tree to weaken. Therefore, in order to rejuvenate weak trees, in addition to strengthening the comprehensive management of soil, fertilizer, water, disease and insect control, etc., in terms of pruning, the main task is to remove some seed-bearing branches, increase the degree of shortening appropriately, and retain strong branches, strong buds, etc. . After several years of this, the tree's vigor can gradually recover.