Detailed Explanation of Key Points on Poplar Sapling Cutting Propagation Techniques
SummarySelect a nursery site with fertile soil, loose texture and good drainage and irrigation. Use 1-year-old robust stumping seedlings, cut them evenly, and store the cuttings well. In spring and autumn, insert the cuttings at a row spacing of about 60cm, at a 45-degree angle to the ground, exposing 1-2 buds. About 4 plants can be inserted per meter, and about 4800 plants per mu. Never insert the cuttings upside down, and water promptly after inserting.
1. Choosing a Good Nursery Site
The nursery site should be chosen in an area with flat terrain, good drainage and irrigation, relatively fertile soil, loose texture and convenient transportation. Before winter, plow the soil deeply to 25-30cm for freezing and weathering, and apply 6000 jin of base fertilizer per mu. In the second spring, prepare the land and make beds again. Choosing a nursery site with relatively good soil helps improve the survival rate of the seedlings.
2. Collecting Stems and Cuttings
It is suitable to use 1-year-old stumping seedlings. The branches should be free of pests and diseases and grow robustly. The cuttings should have a diameter of 1-2.5cm and a length of 15-18cm, preferably retaining 3-5 robust buds. Use a kitchen knife to cut the top flat and cut the tail into a horseshoe shape. During this process, avoid splitting the cut. Then store the cut cuttings promptly to prevent air-drying and water loss, which would reduce the survival rate.
3. Inserting Cuttings
Poplar cutting propagation can generally be carried out in both spring and autumn, but in spring the cuttings should be inserted early. A line can be stretched at a row spacing of 60cm for inserting cuttings. The cuttings should form a 45° angle with the ground, with 1-2 buds exposed above the ground. About 4 cuttings can be inserted per meter, and about 4800 cuttings per mu. During this process, the cuttings must not be inserted upside down, and cuttings of different thicknesses should be inserted separately to keep growth neat and uniform.
4. Fertilizer and Water Management
After inserting the cuttings, water lightly once promptly. Later, water once every 7 days. After the seedlings are established in early to mid-May, watering can be combined with fertilization. After that, water about every 13 days according to soil conditions. Generally, fertilize twice in June-July. About 10 waterings are needed each year. In early September, water thoroughly for the last time, then stop watering, to promote lignification of the poplar seedlings and prevent excessive vegetative growth, which helps them overwinter safely.
5. Bud Removal and Weeding
After the seedlings are established, carry out loosening of the soil and weeding about 2 times. Generally, lateral branches grow from the small leaf axils of poplars. At this time, the young buds need to be removed immediately. Throughout the entire growth process, bud removal should be carried out at least 3 times. The 1st time can be chosen in mid-to-late May; if more than two shoots or buds appear, only 1 plant needs to be retained. The 2nd time can be chosen at the end of June, removing all sprouted lateral branches. The 3rd time can be chosen in mid-to-late July.
6. Pest and Disease Control
1. Nursery preparation: Before raising seedlings, prepare the land. Per mu, use 1.5-2 kg of 50% methyl parathion granules mixed with fine soil and scatter it into the soil to control underground pests.
2. Cutting seedlings: Use a mixed solution of 50% carbendazim and 15% thiophanate-methyl in a 1:1 ratio diluted 200-250 times, and soak the seed roots for 1-2 hours. This can effectively control black spot disease and root rot.
3. Sprouting: Use a 1200-fold dilution of 50% methamidophos to spray the roots and stems, which can effectively control pests and diseases of young buds.
4. Growth period: In July-August, use a 1500-fold dilution of 50% phoxim and a 500-fold dilution of carbendazim to control pests and diseases such as stinging nettle caterpillars and brown spot disease.