According to Catalpa bungeana cultivation experts, the flowering period of Catalpa bungeana is May-June.
growing environment
Light-loving tree species, warm and humid climate, not cold-resistant, suitable for areas with annual average temperature 10- 15 degrees and annual precipitation of 700- 1200mm. Strong ability to take root and sprout. It grows rapidly in deep, moist, fertile and loose neutral soil, slightly acidic soil and calcareous soil, and can grow normally in mild saline-alkali soil, but it grows poorly in dry and barren gravel soil and poorly structured clay, even showing the pathological state of small old trees. It is sensitive to soil moisture, not drought-resistant, not water-resistant and wet-resistant, and cannot grow in places with less accumulated water and high groundwater level (below 0.5 meters). It has strong resistance to toxic gases such as sulfur dioxide and chlorine. Seedling growth is relatively slow.
distribution range
Distributed in China, Hebei, Henan, Shandong, Shanxi, Shaanxi, Gansu, Jiangsu, Zhejiang and Hunan. Cultivated in Guangxi, Guizhou and Yunnan. The type specimens were collected from Beijing.
breeding method
sow seeds
Seeds were collected from 15-30-year-old robust mother tree. When the fruit changed from yellow-green to grayish brown and slightly cracked at the top, it indicated that the seeds were mature, so small branches could be cut off and the fruit could be picked. Sow in spring in March. Before sowing, soak the seeds in 30-degree warm water for 4 hours, take them out to dry, mix them with 3-5 times of wet sand, pile them in the house to accelerate germination, and sprinkle water regularly to turn them over to make the internal and external temperatures uniform. After about 10 days, 30% of the seeds can be planted when their mouths are cracked. The row spacing is 20-25cm, and the sowing amount per mu is1-2kg. Water should be poured on the soles of the feet before sowing, and fine soil and sand should be covered after sowing, with a thickness of about 0.5 cm, and it is advisable to bury the seeds slightly. Finally, put a plastic sheet on the bed to shade the sun. After all the seedlings grow, remove the mulch. In the future, we should strengthen the management of fertilizer and water, loosen the soil and weed.
Cutting propagation method
Select 1 year-old seedlings as seed cuttings, cut them into cuttings of 15-20cm, bundle every 50 cuttings or 100 cuttings, and stand them in an open-air silo, with one layer of cuttings and one layer of wet sand. Cover the pit with 20cm soil, and thicken the soil layer when cold. A straw stalk is erected every 1 m in the pit for ventilation. Check frequently in early spring to prevent the cuttings from becoming moldy due to the rising ground temperature. Cutting in March-April, with the row spacing of 20-30 cm, and the height of seedlings in that year can reach more than 1- 1.5 meters. ..
Bury roots
Collecting root strips with the diameter of 1-2 cm, cutting into root segments with the length of 15-20 cm, and making them flat on the top and inclined on the bottom. Digging roots should be carried out after thawing in spring and before germination, so as to dig, cut and bury strips. Rooting in autumn should be stored in wet sand until spring. From late March to early April, before sowing 15 days, choose a sunny place, and mix the seed strips with wet sand to accelerate germination. The thick and thin strips are buried in stages to ensure the orderly emergence of seedlings. Oblique burial: the big head is upward, the small head is inclined downward by 40, and the upper end of the root is flat with the ground. After burial, cover the soil 1- 1.5cm and tamp it. Arable ridge in arid area, height 15-20cm. When the bud just germinates, the ridge should be opened to avoid damaging the bud. The roots that can't tell the difference between the upper and lower heads are buried horizontally. Spread the roots in the ditch, cover with soil 1- 1.5cm, and tamp. When the seedling height is 10 cm, the buds are removed, leaving only well-developed and prosperous buds.
transplant
In late autumn and early spring, when the trees are budding, Catalpa bungeana seedlings are used as rootstocks, and the strong branch buds of the year are collected from the excellent mother plants of Catalpa bungeana, and the seedlings are grafted with xylem. Catalpa bungeana grafted seedlings have strong adaptability, fast growth and good stress resistance, and the grafting survival rate is as high as 85% to 90%.