Cultivation method of fast-growing ash tree

Select plots with rich soil nutrients, high organic matter content, loose structure, good air permeability, pH value of 7.5 ~ 8.0 and saline-alkali content less than 0. 1%. Nursery requires flat terrain, good irrigation and drainage conditions and few weeds in the field. Heavy sandy loam and heavy clay land should be improved, and light sandy loam has good seedling raising effect.

Second, the soil treatment:

1. Before sowing, apply sufficient base fertilizer in combination with soil preparation. Generally, 4000 ~ 5000 kg of decomposed farmyard manure and 25 kg of diammonium are applied to 667 square meters, and then evenly mixed and spread in the ground, and deeply ploughed for 30 cm.

2. When applying farmyard manure, 2 ~ 3kg of 5% phoxim granules can be added to the manure, the medicine can be mixed with fine soil, scattered in the nursery, and then ploughed to eliminate underground pests. Apply 15 ~ 20kg ferrous sulfate every 667m2, mix it with 20 times of fine soil, and spread it evenly on the seedbed to prevent seedling blight.

Thirdly, soil preparation:

1. Strictly prepare the soil before sowing to reach the standard of fine, broken and flat.

2. Make the nursery land into a border field of 20 square meters or 40 square meters according to the irrigation direction. The border field is flat, and the seedbed is 2m wide and 10m long, or 4m wide and 10m long.

Four, seed treatment:

Low-temperature stratification accelerates germination: choose a place with high terrain, good drainage and large shade to dig trenches. In principle, the depth of the ditch is below the permafrost and above the groundwater level, and the width of the ditch is 80 cm. The length of the ditch depends on the number of seeds. The ratio of Fraxinus mandshurica seeds to wet sand is 1: 2 ~ 3. First, lay a layer of wet sand with a thickness of 10 cm at the bottom of the ditch, and then fully mix the seeds with the wet sand and put them into the ditch. The seed sand is 50 ~ 70 cm thick, and the wet sand is covered at 10 cm above the ground, and then covered with soil to make the top look like a roof. Put a straw every 0.7 ~ 1 m to facilitate ventilation, and the general treatment time is 60 ~ 80 days.

Five, seedling tending management:

In the process of seedling growth, strengthening seedling tending management is the key to cultivate strong seedlings.

5. 1 irrigation and drainage

According to the different stages of seedling growth, the irrigation time and quantity are reasonably determined. During the germination period of seeds, the bed surface should be kept moist and irrigated many times. After the seedlings come out, the cotyledons are fully unfolded and enter the vigorous growth period. Irrigation amount should be more and times should be less. Irrigation should be done every 2 ~ 3 days 1 time, and each time it is permeable. Irrigation time should be carried out in the morning and evening. Drainage should be done in time when it rains in autumn.

5.2 Loosening and weeding

In line with the principle of "early weeding, small weeding and large weeding", weeds should be removed in time, and weeding should be carried out after rain or irrigation. When seedlings enter the peak growth period, loosen the soil, shallow at the initial stage and slightly deep at the later stage, so as not to damage the root system of seedlings. In the seedling hardening period, in order to promote the lignification of seedlings, loosening soil and weeding should be stopped.

5.3 Topdressing

Fertilization of seedlings should be based on base fertilizer, but its nutrition may not meet the needs of seedling growth. In order to make the seedlings grow fast and strong, chemical fertilizer should be applied during the vigorous growth period of seedlings. Nitrogen fertilizer should be applied at seedling stage, and more nitrogen fertilizer, potassium fertilizer or several fertilizers should be applied at the rapid growth stage of seedling stage. In the late growth stage, nitrogen fertilizer should be stopped and potassium fertilizer should be applied more, and quick-acting fertilizers (such as urea, potassium dihydrogen phosphate and calcium superphosphate) should be the main topdressing, with fewer times.

5.4 seedlings

In order to adjust the density of seedlings, thinning and replanting are needed. In the seedling raising of Fraxinus mandshurica seeds, it is generally done twice, 1 time when the seedlings grow two pairs of true leaves, and the second time when the seedlings' leaves overlap each other. Intercropping seedlings should be superior and inferior, and seedlings with poor growth and development, pests and diseases, mechanical damage and excessive density should be eliminated. It is best to carry out thinning when the soil is wet after rain.

5.5 Pest control:

In pest control of Fraxinus mandshurica seedlings, we should start with winter ploughing, soil disinfection, careful selection, seed disinfection, rational fertilization, timely early sowing and management to prevent the occurrence of pests and diseases. The main disease of Fraxinus mandshurica is sooty blotch, and the main pests are leaf roller moth and longicorn beetle. The former harms young leaves, while the latter eats branches. Find pests and diseases and eliminate them as soon as possible.