Hardwood cutting technique of Robinia pseudoacacia

1. Collection and storage of seed strips

At the end of November, the fine clone seed strips of the same year were collected from the ear-picking nursery, or the stems of the seedlings used for cutting and afforestation were collected, and the short spikes of 18-20cm were cut, leaving at least 2 buds per cuttage. The distance between the upper cut and the upper bud is 1. 0-1.5cm, and the lower cut is cut into a single Mallet shape. After 50 cuttings are cut, put them in a cool outdoor place and bury them with clean fine river sand (water content 60%). A layer of cuttings, covered with a layer of sand, try to make each stick see sand. Cover each layer of cuttings with a sand thickness of 3-5cm, and then place another layer of cuttings. Repeat the practice on the first floor. The number of cuttings stored in each place depends on the size of the site, but the height of storage is generally no more than 4 floors. The top layer is covered with river sand and its thickness is not less than that of 10cm.

2. Cuttage seedling

In the middle and late April of the following year, cuttings began to grow seedlings after the soil was thawed. Before cutting, the seedling land will be leveled and raked fine, and 3-5 cubic meters of organic fertilizer will be applied every 667 square meters. The cutting density is 20cm × 40cm, 8300 cuttings per 667m2. Using border cultivation, the width of the border is 1.2m and 3 rows are planted in each border. The depth of the cutter is flat with the ground (oblique or straight). After inserting, keep your feet firm, and then pour enough water. After watering, the upper end of the cuttings should expose the ground l-2cm, and 5-7 days after insertion, the seedling bed should loosen the soil, which is beneficial to increase the ground temperature, maintain moisture and promote the rooting of cuttings. Conditional units or individuals can be covered with plastic film, the seedling effect will be better.

3. Wiping buds to promote the rooting of cuttings

Robinia pseudoacacia cuttings began to germinate 15-20 days after cuttage, and the germination rate reached 100%. According to the biological characteristics of a large number of regenerated hidden buds of Robinia pseudoacacia, in order to reduce the nutrient consumption of cuttings and promote underground rooting, the aboveground buds of cuttings should be wiped out twice in time. For the first time, the buds are cut off from the base when the buds reach 3-5cm. Do not loosen the cuttings when wiping buds, but water them once after wiping them. After the first sprouting, with the gradual rise of air temperature, the hidden buds on Robinia pseudoacacia cuttings continue to germinate and grow after 7-10 days, and the height can reach 3-5cm, so the second sprouting should be carried out. The specific practice is the same as that of the first time. After wiping buds for the second time, the hidden buds on the cuttings continue to germinate and grow. At this time, attention should be paid to protection and no longer sprouting. After two times of sprouting, a large number of calli were formed under the cuttings, and the cuttings began to take root with the rise of temperature and the growth of aboveground parts.

4. Management

For hardwood cuttings of Robinia pseudoacacia, except for two complete sprouting, the management measures in other aspects are basically the same as those of general tree species. It mainly includes the following contents: timely watering, fertilization, loosening soil, weeding, prevention and control of diseases and insect pests. Because there are many hidden buds in each bud eye of Robinia pseudoacacia, 2-3 buds can still grow at the upper end of each cuttings, although they have been completely smeared twice. Therefore, it is necessary to fix the seedlings and wipe the buds. When the seedlings grow to 15-20cm, each plant chooses a bud with good growth and strong growth to retain, and the rest of the buds are erased. After setting the seedling, topdressing once, applying carbon ammonia 50kg every 667m2, and watering once.