The Latest Larch Planting Techniques and Methods Tutorial

Larch is a type of pine, a deciduous tree of the genus Larix in the family Pinaceae, a major forest constituent species in the forest regions of Northeast China and Inner Mongolia, one of the three major coniferous timber tree species in the Northeast region, with a very wide natural distribution, and the most cold-tolerant among coniferous tree species, with its vertical distribution reaching the uppermost limit of forest distribution. Let us now take a look at larch planting techniques!

Cultivation Value of Larch

Larch wood is heavy and solid, with high compressive and bending strength, and is resistant to decay, with high technological value, making it an excellent timber for utility poles, railway sleepers, bridges, mine props, vehicles, construction and more. The tree is tall and upright, with an attractive crown shape, a very well-developed root system, and strong resistance to smoke, making it also an excellent landscaping tree species. Larch arabinogalactan is obtained by extracting larch genus wood with water or dilute alkali solution, and is a low-viscosity, highly dispersible gum, mainly used in medicine, food and other fields.

Growth Habits of Larch

Larch is a light-demanding, strongly heliophilous tree species with strong adaptability and a very wide tolerance range for soil moisture and soil nutrient conditions. It grows best under moist, well-drained, well-aerated, deep and fertile soil conditions. It can also grow on dry, barren sunny mountain slopes or in waterlogged wetlands or low-lying areas with standing water year-round, but its growth is poor there. It is tolerant of low temperatures and cold, and generally can grow normally even at a minimum temperature of -50°C. It is distributed in the Greater and Lesser Khingan Mountains, Laoyeling, Changbai Mountains in the Northeast, northwestern Liaoning, northern Hebei, Shanxi, the Qinling Mountains in Shaanxi, southern Gansu, northern, western and southwestern Sichuan, northwestern Yunnan, southern and eastern Tibet, the Altai Mountains and eastern Tianshan Mountains in Xinjiang, often forming large areas of pure forest, or growing mixed with other coniferous and broadleaf tree species.

Larch Seedling Cultivation

1. Nursery site selection: Choose a site with convenient transportation, flat terrain, good drainage and irrigation, deep soil layer, loose soil texture, and relatively fertile neutral or slightly acidic sandy loam or light loam for raising seedlings. Prepare the land in winter, apply 750 kg of organic fertilizer per mu, plow deep to 30 cm, evenly spray a 1:10 ferrous sulfate solution before sowing, and after it dries, rake level and make beds. The beds should be 15 cm high, 1 m wide, with 25 cm between beds.

2. Seed treatment: Before sowing larch seeds, soak the seeds in a 0.5% potassium permanganate solution for disinfection for 4 hours, wash them clean with water, then place them in 45°C warm water to soak for 24 hours. Remove them, dry them slightly, then mix them with river sand three times the volume of the seeds, and place them in a germination pit to force germination. The germination pit should be dug in a sheltered, sunny spot, 50 cm deep and 50 cm wide, covered with plastic film, and covered with straw curtains at night. Turn the seeds evenly once a day, and sow once 30% of the seeds have cracked open.

3. Sowing techniques: Sow when the surface temperature is above 10°C. The sowing rate is 4-4.5 kg per sq m. Before sowing, the seedbed should be watered thoroughly. Use drilling, with row spacing of 10-15 cm and furrow depth of 1 cm. After sowing, cover with 1 cm of fine sandy loam, and cover with a layer of rice straw. After covering with straw, the ground should preferably not be visible, and water should be sprayed immediately. Thereafter, spray water in small amounts several times a day, always keeping the bed surface moist. Begin removing the straw when 30-50% of the seedlings have emerged, and remove all the straw once the seedlings have fully emerged. Straw removal should be done on cloudy days or in the evening, and water should be applied promptly after removal.

4. Seedling stage management: After emergence, water timely in small amounts several times, keep the seedbed moist, and pay attention to loosening the soil and weeding. Weeding should be combined with soil loosening, and a shade frame must be built above the seedbed to maintain light transmittance at 60-70%. The main disease of larch seedlings is damping-off, and the insect pests are white grubs and mole crickets, which should be controlled during the seedling cultivation process.

Larch Planting Techniques

1. Site selection and land preparation: Generally, pit-shaped, fish-scale pit and horizontal trench land preparation methods are used. On newly cutover sites and abandoned farmland with fewer weeds, and on sites with sparse shrubs, use pit-shaped land preparation with a specification of 40 cm × 40 cm × 30 cm. On barren hills and old cutover sites, and on sites with dense shrubs and weeds, brush cutting should be carried out first before land preparation. The specification for fish-scale pit land preparation is 50 cm × 50 cm × 40 cm, or horizontal trench land preparation may be used, with a specification of trench length 70-100 cm, width 40-50 cm, and depth 30-40 cm.

2. Planting density: Use 2-year-old grade 1-2 qualified seedlings for afforestation. For afforestation on sites with better site conditions, the planting density should preferably be 1600-1700 trees per hectare, with a spacing of 2 × 3 m. For afforestation on sites with relatively poorer site conditions, the planting density should preferably be 2500 trees per hectare, and either a spacing of 2 × 2 m or a spacing of 1.6 × 2.5 m may be used.

3. Fertilizer and water management: After planting larch, apply water twice within one week, after which the soil can be loosened and moisture conserved. Water once more in early May, and thereafter do not water unless the weather is dry. Apply fertilizer once in June, and apply ferrous sulfate once in August. Apply by digging pits beside the plants and applying in spots. For soil loosening and weeding, this can be done once every 20 days, and should be done carefully and thoroughly, generally to a depth of 4 to 5 cm, with even hoeing, loose soil with no clods, and weeds completely hoed and picked clean.

4. Disease control: Before the peak period of ascospore release in spring and summer, spray 1:1:100 Bordeaux mixture, 50% Tuzet 500-800 times solution, 70% Dexon 500-800 times solution, 65% Zineb 500 times solution, 45% Amobam 200-300 times solution. In closed young forests or heavily diseased mature forests, apply 621 smoke agent, chlorothalonil smoke agent or sulfur smoke agent.