How to grow Pinus bungeana from seed? Latest technical method tutorial
Pinus bungeana is a tree species endemic to China, with a graceful form and unusual bark, suitable for ornamental use; its wood can be used for house building, furniture, stationery and so on. In cultivation it is generally propagated by sowing. The nursery site should preferably be a sandy loam with good drainage, flat terrain and deep soil. Let us take a look at Pinus bungeana seedling-raising techniques together!
Nursery site selection for Pinus bungeana
Pinus bungeana seedlings are afraid of waterlogging, so the nursery site should be chosen as a flat plot with irrigation and drainage conditions. Heavy clay soil, saline-alkali soil and low-lying waterlogged land are not suitable as nursery sites. Prepare the land carefully: the nursery site should be deep-ploughed, levelled and raked fine, with sufficient base fertilizer applied, such as rotted barnyard manure or compost. Calcium superphosphate can also be mixed with cake fertilizer or farmyard manure for better results. Before land preparation, spread 10 kg of ferrous sulfate powder per mu, and turn it into the soil for sterilization and disinfection. After the land is prepared, make seedbeds running north-south, with bed ridges 25 cm high and beds 1 m wide, ready for sowing.
Sowing Pinus bungeana seeds
1. Seed germination: To treat Pinus bungeana seeds, soak them in Bordeaux mixture for disinfection. Before sowing, soak the seeds in warm water (50°C to 60°C) to promote germination, or use sand stratification to promote germination. When the number of cracked seeds reaches 50% of the total number of seeds, they can be sown. In this way the seedlings emerge strong and uniform, and generally they can sprout and emerge in 15 to 20 days.
2. Seed sowing: Sowing is generally best done 10 to 15 days after the soil thaws (late March to early April). Before sowing, water the bed surface thoroughly. Sow 1 to 1.5 kg per 10 sq m, which can produce about 1500 seedlings, using wide-row drilling or broadcasting. After sowing, cover with fine sandy soil 1 to 1.5 cm deep. Per mu, use 125 g of prometryn plus 250 g of 25% wettable nitrofen, mix with 25 kg of water, and spray it on the seedbed with a sprayer for weed control. Finally, build a small arched shed over the bed surface to increase temperature and retain moisture, improving the emergence rate. No watering is needed before emergence.
3. Management after sowing: Because mice like to eat pine nuts, before building the arched shed and covering it with film, scatter some rat poison on the bed surface. For seedling-stage management, after the seedlings emerge fully, gradually increase the ventilation time of the seedbed, and strengthen their resistance through hardening. Pinus bungeana likes light, but the seedlings are relatively shade-tolerant. After removing the film, shade netting should be put up immediately to prevent damage from high temperature, sunscald and damping-off disease.
Seedling management of Pinus bungeana
1. Watering and weeding: During long droughts without rain or in high summer temperatures, water in time. Weeding should follow the principles of removing early, removing small and removing thoroughly. Weed between plants by hand to avoid damaging the seedlings. After weeding broadcast-sown seedlings, cover the soil appropriately to prevent cracks. For drilled seedlings, combine weeding with loosening the soil. Thin and fill in seedlings at the same time, and also drain water in time.
2. Rational fertilization: For Pinus bungeana seedlings, base fertilizer should be the mainstay and topdressing supplementary. From mid-May to the end of July, during the peak growth period, carry out 2 to 3 topdressings, mainly with nitrogen fertilizer. Apply rotted human excrement or pig manure at 3 loads per mu, mixed with about 20 loads of water; rotted cake fertilizer at 5 to 15 kg per mu, mixed into about 15 loads of cake fertilizer water; apply about 4 kg of urea per mu. In the later growth stage, stop applying nitrogen fertilizer and increase phosphorus and potassium fertilizer to promote lignification of the seedlings. A 0.3% to 0.5% potassium dihydrogen phosphate solution can also be sprayed on the leaves.
3. Timely transplanting: Pinus bungeana seedlings grow slowly and are suitable for dense planting. If large-sized seedlings are to be continually cultivated, then 2 to 3 more transplantings are needed before final planting. Two-year-old seedlings can be transplanted with soil in early spring before the terminal buds have begun to sprout, with a plant and row spacing of 20 to 60 cm, without damaging the terminal buds. After planting, water twice in succession, then water again after 6 to 7 days. Four- to five-year-old seedlings can undergo a second transplanting with a soil ball, with a plant and row spacing of 60 to 120 cm. After they survive, keep the soil around the roots loose, apply 100 to 120 kg of rotted organic fertilizer per plant, water thoroughly after covering with soil, and then strengthen management to promote growth and cultivate strong seedlings.
4. Pest and disease control: After sowing, pay attention to damage to seedlings by bean seed fly larvae; the base fertilizer applied must be fully rotted and crushed. The pine aphid damages the tender branches and needles of seedlings and easily leads to sooty mold, causing weakened tree vigor and even death. In the early stage of damage, spray 50% phoxim emulsion, adding 2000 kg of water per kg.