Methods for Rooting Transplanted Nursery Stock and Remedial Measures for the False Death Phenomenon

Transplanting can expand the nutrient space for nursery stock growth and improve the survival rate of greening. So do you know how transplanted nursery stock take root? If it shows the false death phenomenon, what remedial measures should be taken? Here is a detailed introduction.

How do transplanted nursery stock take root?

1. Mechanical treatment.

(1) Peeling: generally speaking, fruit tree varieties with well-developed cork tissue on the branches are more difficult to root. Before cutting, first peel off the epidermal cork layer to enhance the water absorption capacity of the cuttings, which can promote root formation.

(2) Longitudinal scoring: use a knife to cut a wound 2 to 3 cm long at the base of the cutting, reaching the phloem, which can form neatly arranged adventitious roots between the longitudinal wounds.

(3) Ring peeling: 15-20 days before taking the cuttings, make a ring peel of bark (3-5 cm wide) at the base of the branch on the mother plant intended for use as a cutting, which helps promote adventitious roots.

2. Treatment with biological agents. The agents can significantly promote rooting of nursery stock, enhance the root's absorption and anchoring capacity, raise ground temperature, promote early sprouting, and turn weak seedlings into strong seedlings. During planting and transplanting, seedlings recover and root quickly, and the agents can prevent excessive vegetative growth and resist disease and stress. Scoring the base of the cuttings longitudinally before treatment gives better results.

3. Prepare a good nutrient substrate. Before cutting, choose materials and substrates that are easy to aerate, nutritious, free of pathogens, and free of pests as the seedbed, such as fine river sand, perlite, and burnt soil. The seedbed should be moist but not waterlogged.

4. Use high-quality cutting varieties at the right time. Different cuttings vary in how easily they root. Easy-to-root ones include Chinese fir, willow, and grape. Less easy-to-root ones include pear and magnolia; difficult-to-root ones include pine, walnut, and lychee. For the same variety, as the branch age increases, rooting ability declines. Branches are plump in autumn and winter, and their rooting ability is stronger than in spring after the dormant period.

5. Control the microclimate. The microclimate mainly refers to the light, air, temperature, and humidity of the cutting nursery. Light should be mainly slightly dim, and oxygen should be appropriately increased to facilitate the life activities of the cuttings. The temperature should be 23-25°C, and the relative air humidity should be 70%-80%.

6. Heating treatment. Generally, nursery stock begins to sprout at an air temperature of 10-12°C, while for cutting rooting, a soil temperature of 18-25°C is most favorable. Early spring cuttings often have difficulty rooting because the soil temperature is too low. You can artificially raise the temperature of the lower growth part of the cuttings, while spraying water and ventilating to lower the ambient temperature where the buds at the upper end of the cuttings are located.

If it shows the false death phenomenon, what remedial measures should be taken?

After nursery stock (including fruit trees) is planted, it does not sprout for a long time, but if you break a branch and look, the inside is still tender green, and the branch is also soft, not dried up. After a few months, or even into the second year, it then sprouts and grows. This phenomenon is called false death. The causes of the “false death” phenomenon in nursery stock are analyzed as follows:

1. Poor nursery stock quality and poor root growth: the nursery stock is thin and weak, with many broken root wounds and few roots. After the upper part sprouts leaves and shoots, the root system cannot supply the needed water and nutrients in time, causing the leaf tips to die.

2. Because the irrigation berm is built too small and too shallow, the irrigation amount is insufficient. Although water has been applied three times, the soil ball has not absorbed water thoroughly. Or because the soil ball is too large and too dry, the three waterings have not soaked through, causing the root system to lack water during the seedling recovery period, resulting in the nursery stock not sprouting, or the leaves beginning to wilt and dry up and fall.

3. Soil compaction and lack of oxygen or waterlogging and root rot: long-term drought can cause nursery stock to wilt, while low-lying land often causes nursery stock roots to rot due to rain accumulation. Therefore, after planting nursery stock, the settling water must be watered thoroughly. And in low-lying waterlogged areas, drainage ditches must be opened well.

4. When shaping, leaving weak buds or mostly blind buds (bud eyes that cannot produce shoots): thus the new buds cannot emerge in time, causing the nursery stock to delay sprouting and rooting, resulting in false death.

In addition, unreasonable trunk determination can also cause the false death phenomenon in newly planted nursery stock. To prevent false life and false death in nursery stock, we must start from the following aspects:

1. The soil ball should be dug out and repackaged as early as possible, and the planting surface elevation should be raised for replanting.

2. When the second situation occurs, immediately enlarge the tree hole and raise the irrigation berm. During heavy irrigation, poke several holes in the soil ball so that the inside of the soil ball absorbs water thoroughly. After 3-4 days, irrigate with rooting powder to promote rapid root formation. Pay close attention to the progress of rooting and leaf unfolding. If the effect is not ideal, the branches should be appropriately shortened, and remedial measures such as continued irrigation with rooting powder and nutrient solution infusion should be taken.

3. If, after digging open the tree hole, the soil in the hole is found to be too wet but the root system has not turned black and rotted, remedial measures such as opening the hole to dry the soil ball, replacing the planting soil, and appropriately controlling the number and amount of irrigation can be taken. If water accumulates at the bottom of the hole, then from the bottom of the hole downward, drill several holes and fill them with sand, or install drainage pipes below the soil ball leading outside the tree hole for discharge, ensuring that no water accumulates in the tree hole.

4. Select high-quality strong seedlings for planting. The nursery stock is required to be robust, with plump bud eyes, fresh and lively, and well-developed roots. At the same time, when lifting seedlings, do not damage the roots too much; keep as many roots as possible.

5. When planting seedlings, the root system must not directly contact the fertilizer. Spread a layer of loose fine soil over the fertilizer, then plant. Before planting, use a 100-150 times dilution of Shengtaijian to sterilize the soil hole, and use a 1:1 mixture of Sheng Genbao and Shengtaijian to carry out rooting and sterilization on the soil ball, increasing the survival rate by 80%.

6. For young trees, trunk determination should depend on the tree and its buds. Within the shaping zone, plump buds must be selected and retained, avoiding weak buds and blind buds.