Seedling raising technique of Tianshan spruce

I. Tillage of seedling land

The loam and sandy loam with better drainage and irrigation conditions should be selected for spruce seedling cultivation. Spruce seeds are small, only by intensive cultivation can we improve the sprouting rate of seedlings and cultivate high-quality strong seedlings. The soil was ploughed deeply in autumn, with a depth of 250.30 cm, and 3 tons of base fertilizer was applied every 667m2. Combined with soil preparation for soil disinfection, 0.1% carbendazim or methyl thiophanate solution was sprayed with 1 kg solution for every 667 square meters. Make the bed with fine rake in spring, strive to break the soil finely, and irrigate the bottom water 3 days before sowing.

2. Selection of seeds

The seeds are selected by wind and water before sowing. The purity of the seeds selected twice should be more than 80%. About 5 days before sowing, soak the seeds with 0.5% ferrous sulfate solution for 3 hours. When the seed shell is iron black, soak it in 25 ℃ warm water for 24 hours, then remove it and place it in a wooden box, spray it with 30 ℃ warm water 5 times a day to keep warm and moisturizing. After 4 days, when more than 80% of the seeds are cracked, they can be sown with fine sand.

Third, sowing time

The autumn frost in our nursery is early, so it is suitable to sow seeds in spring. The ground temperature rises day by day in spring, and the sowing is usually in the middle of May. The sowing rate is 40 kg per 667 square meters, the wide strip is used, and the width distance and sowing width are 10 × 20 cm. Rake the bed flat, put the seeder on the bed, spread the seeds evenly, and then cover a layer of sterilized mixed sawdust (1 part of saw foam, 3 parts of soil) with a thickness of 0.5 cm. After covering the soil, gently suppress, and then cover the bamboo curtain.

IV. Seedling management

1. Shade

Tianshan spruce is a shade-tolerant tree species, especially in the seedling stage, which needs certain shading conditions, so the shed shading method is adopted. After all the spruce seedlings are out, the bamboo curtain can be rolled up from 6 pm to 9 am every day. On August 30, all bamboo curtains were removed to promote seedling growth and Lignification.

two。 Weed

In order to reduce the evaporation of soil moisture, loosen topsoil and increase soil permeability, there should be no weeds in the seedling bed.

3. Pest control

When a large number of seedlings are unearthed, 1% carbendazim and methyl topiramate can be sprayed, with a dosage of 60 kg per 667 square meters. After that, it was sprayed once every 7-8 days, for a total of 4 times.

4. Irrigation

According to the weather and soil conditions, sprinkle water with a spray can at the right time to keep moist.

5. Overwintering

Spruce seedlings are young and tender, with low Lignification, weak cold resistance and easy to suffer frost injury, especially the freezing injury and physiological drought in early spring, which often cause a large number of seedlings to die, so effective measures should be taken to prevent freezing in winter before snow. Before the soil froze, the sawdust and sheep dung were screened and disinfected, and a mixture of 1 ∶ 3 (1 part of sawdust and 3 parts of sheep manure) was evenly covered on the seedlings to cover the top of the seedlings.