Detailed Explanation of Key Techniques for Direct Seeding Afforestation of Siberian Apricot
Direct seeding afforestation of Siberian apricot requires little investment, forms forests quickly, has low costs, is simple and easy to carry out, and moreover delivers very considerable benefits. Its development prospects are extremely broad, and it is one of the important ways for people in mountainous areas to build wealth.
1. Time and method of direct seeding Direct seeding afforestation of Siberian apricot is divided into two types: spring sowing and autumn sowing. ① Autumn sowing: for autumn-sown seeds, soak the seeds in 50-60°C water for 24-48 hours, remove them and rinse repeatedly with clean water, then dress the seeds with 10% zinc phosphide or another repellent (to prevent rodent damage), and then sow. ② Spring sowing: for spring-sown seeds, after the beginning of winter, soak the seeds by the above method, then mix them with sand at a seed-to-sand ratio of 3:1, store them in a soil pit dug in advance, generally about 1 m from the ground surface, cover with straw and similar materials, then cover with soil for winter storage. At the end of the following spring in March, open the soil pit, take the seeds out and sow them.
2. Afforestation site preparation and sowing rate Use methods such as horizontal trenches or fish-scale pits for direct seeding afforestation, with a plant-to-row spacing of 1.5 m x 2 m, that is, dig more than 220 pits per mu. Sow 3-5 seeds per pit, then cover with soil immediately after sowing to a thickness of 2-3 cm; first backfill with topsoil, then tread firm, and where conditions permit irrigate thoroughly to the bottom.
3. Seedling-stage tending and management Water promptly when there is drought at emergence in spring or drought during the dog days. Carry out weeding, soil loosening and other management promptly. When the seedlings grow to 30 cm tall, select 1 strong seedling free of pests and diseases to keep, and transplant the remaining seedlings with their soil balls into empty planting holes, so as to ensure the survival rate of the afforestation. In early June, preferably before rainy days, apply 0.1 kg of urea as a topdressing to each plant. Let 1-year-old Siberian apricot grow freely; in winter, apply repellent to the trunk to prevent gnawing by rodents and rabbits.
4. Training and pruning When the young tree grows to 1 m tall, determine its trunk height at 60-80 cm, mainly by heading back. In the initial fruiting stage, cut strong vigorous branches back to 2/3, moderate branches to 1/2, weak branches to 1/3, and severely head back extremely weak branches. In the full fruiting stage, renew the fruiting branch groups promptly, thin out branches trailing on the ground and branches with extremely weak fruiting capacity; at the same time thin out large branches in the upper canopy and water sprouts, crossing branches within the canopy, overlapping branches, and severely light-blocking drooping branches. Before flowering, do a follow-up pruning, heading back weak branches with many flowers and thinning out excessive flower buds. At flowering, combine with artificial pollination to thin out late-opening inferior flowers. To increase the pollination rate, where conditions permit, place @#@255@#@1 box per 10 mu; alternatively, on sunny days before 10 a.m. or after 3 p.m., spray a 0.4% borax aqueous solution onto the flowers.
5. Pest and disease control For pest control, before germination in early spring spray 50% monocrotophos 1000x solution, or fenvalerate 800-1000x solution, to eliminate overwintering pest sources. After fruit set, use aphid-killing 1500x solution to control green peach aphid and almond bee. For gummosis control, scrape off the gum, then disinfect the wound with 5-degree lime sulfur mixture. For bacterial shot hole disease, after the leaves unfold, spray 65% zineb or 65% ziram 300-500x solution. For red wart branch blight, once found, promptly prune out diseased branches, apply 5-degree lime sulfur mixture to the wounds, and burn the diseased branches in a centralized manner.