Detailed Introduction to the Latest Propagation Methods for the Japanese Pagoda Tree

The Japanese pagoda tree, also known as Chinese scholar tree, huairui, douhuai, baihuai, xiyiehuai, etc., is a tree of the genus Styphnolobium in the Fabaceae family, native to China and now widely cultivated across the northern and southern provinces and regions, especially common in North China and the Loess Plateau region. It is light-demanding but slightly shade-tolerant, able to adapt to colder climates, with a deep and well-developed root system, and is not demanding about soil. It has extremely high planting value. Let's take a look together at the propagation methods for the Japanese pagoda tree!

Root Burying Propagation of the Japanese Pagoda Tree

1. Seed root preparation: After the Japanese pagoda tree loses its leaves, the seed roots can be introduced, and before planting they should be stored buried in sandy soil. The moisture of the sandy soil must be well controlled, so that the root segments neither dehydrate and dry out, nor become moldy and rot from too much moisture.

2. Land preparation: For seedling cultivation, sandy loam soil with deep soil layers, flat terrain, convenient irrigation and drainage, and no sources of pest and disease infection is best. Apply 2500 kg of livestock and poultry manure per 667 sq m, or apply 50 kg of phosphate fertilizer and diammonium as base fertilizer, and use insecticides such as carbofuran to kill underground pests. The land should be deep-plowed, finely leveled, and raked smooth, with beds about 1 m wide.

3. Seedling cultivation: The seedling cultivation time is early to mid-March in the south, and late March to early April in the north. Select smooth root segments 1 to 2 years old, 5 to 10 mm in diameter, with no traces of pests or diseases, and cut them into 5 to 7 cm lengths for later use. Open furrows along the bed, with a furrow spacing of 50 cm and a depth of 5 cm, then lay the root segments flat in the furrows at a plant spacing of 30 cm, cover with fine sandy soil, water thoroughly to settle the roots, and cover well with plastic film. Seedlings will emerge in about one month.

Cuttage Propagation of the Japanese Pagoda Tree

1. Cutting time: The cutting time is the same as for root burying seedling cultivation, or it may be slightly earlier.

2. Cutting selection: Select lignified hard branches 8 to 20 mm in diameter, cut them into 15 cm long cuttings, cut the upper end flat, 1 to 2 cm from the bud, and cut the lower end into a 45-degree slant, 5 mm from the bud. Divide them into upper and lower ends, tie them in bundles of 50, soak the lower ends in a 50 mg/kg rooting powder solution for 3 to 4 hours, then remove and set aside.

3. Cutting method: Land preparation requirements are the same as above. Insert the branches into the soil at a 45-degree angle at a plant and row spacing of 20 cm × 40 cm, and cover with plastic film along the bed.

Seed Propagation of the Japanese Pagoda Tree

1. Seedling site selection: The seedling site for the Chinese scholar tree should preferably be flat terrain with good drainage and irrigation conditions, fertile soil, and deep loam or sandy loam. It can adapt to neutral, calcareous, and slightly acidic soils, and can grow normally in mildly saline-alkaline soil (with a salt content of about 0.15%), but grows poorly in dry, barren, and low-lying waterlogged nursery sites.

2. Seed treatment

① Soaking method: First soak the seeds in 80°C water, stirring constantly until the water temperature drops below 45°C, then leave for 24 hours and remove the swollen seeds. For seeds that have not swollen, repeat the above method 2 to 3 times until they reach the swollen degree. Cover the swollen seeds with a wet cloth or straw curtain to promote germination. After 1.5 to 2 days, when about 20% of the seeds have sprouted, they can be sown.

② Sand storage method: Generally, seeds are sand-stored 10 to 15 days before sowing. Before sand storage, soak the seeds in water for 24 hours, and bring the sand moisture content to 60%, that is, it forms a ball when held in the hand and crumbles when touched. Mix the seeds and sand thoroughly at a volume ratio of 1:3, place them in a pit dug in advance, and then cover with plastic sheeting. During sand storage, turn the mixture once a day and keep it moist. When 50% of the seeds have germinated, they can be sown.

3. Sowing method: Spring sowing is generally adopted, and in Zhuozhou it is best to sow in early to mid-April. The sowing rate is 10 to 12 kg per mu. Ridge sowing or flat bed sowing can be used. For ridge sowing, the ridge spacing is 70 to 80 cm, the ridge bottom width is 40 to 50 cm, the surface width is about 30 cm, the ridge height is 15 to 20 cm, the sowing width is 10 cm, and the soil cover is 1.5 to 2 cm. Flat bed sowing can also be used, without ridges, with a row spacing of 60 to 70 cm and a sowing width of 5 cm. After sowing, press the soil so that the seeds and soil are closely combined, and cover with film if conditions permit.