What water-saving methods are there for growing chestnuts on hillsides?
Mulching the tree basin with grass
Mulching the tree basin with grass is an economical, convenient and labor-saving technical measure. It can make full use of the weeds growing on hillside terraces and the straw left after crop harvest, and it can both store water and preserve soil moisture and increase soil organic matter, making the soil more permeable to air and water.
Specific method: spread weeds or harvested corn straw over the tree basin from the inside outward. A mulching thickness of 10-15 cm is suitable, and after covering, scatter a small amount of soil on top to prevent it from being blown away by wind and to prevent fire. Add a supplementary mulch once each year, and carry out deep digging once every 3-4 years so that it fully decomposes and increases soil nutrients.
Mulching the tree basin with plastic film
Covering the tree basin with plastic film can both raise soil temperature, favor root growth and promote sprouting, and also significantly reduce soil water evaporation. Covering the tree basin can be done as soon as the chestnut planting operation is completed, and the covered area varies with tree age; at minimum it must not be smaller than the tree basin. After covering with film, press the edges firmly with soil all around to prevent it from being blown away by wind.
Digging holes under the canopy
Digging holes under the canopy is suitable for most chestnut forests on engineered site preparation and for chestnut forests established on relatively steep hillsides.
Specific method: with the trunk as the center, spread outward in a triangular radial pattern and arrange the area under the tree basin into several small pits. The size and shape of the pits vary with terrain; the pits are about 30 cm deep and 30 cm wide, and the number depends on canopy size. The covered area of the pits can extend 2-3 m beyond the outer edge of the canopy. This can effectively control soil and water loss and play a role in conserving water, soil and fertilizer.
Storing fertilizer and water in holes
Storing fertilizer and water in holes is easy to carry out and highly practical. Tests have shown that the yield increase is also very significant.
Specific method: before the tree body sprouts, dig holes around the canopy, with a diameter of 30-40 cm and a depth of 40-50 cm; place a grass bundle previously tied with wheat straw and the like vertically into the hole, and backfill around the grass bundle in the hole with well-mixed fine soil plus a small amount of slow-release compound fertilizer, tamp it down and level the ground, cover the top of the grass bundle with 2-3 cm of soil, water with 4-5 kg, cover the hole with plastic film, and press soil around the edges so that it forms a pot-bottom shape that is low in the middle and high around the edges, with a small hole opened in the center. After covering with film, watering and fertilizing are all done through the hole opening, and at ordinary times it is pressed firm with clods of soil to reduce water evaporation.