Problem description:
30 minutes is urgently needed.
Analysis:
Pine, pine, pine, pine, pine, pine, pine, pine, pine, pine, pine, pine, pine, pine, pine, pine.
Morphology of ascetic monks
Rola Chen
The snow is loose,
The pine trees are tall and straight.
You know, loose and noble,
When the snow melts.
cedar
Cedar. ) G. Don, Pinaceae, Cedar. Cedar is the national tree of Lebanon.
Morphological characteristics of evergreen trees, the big branches are generally flat, irregularly whorled, and the branchlets are slightly drooping. The bark is grayish brown, which splits into scales and peels off when it gets old. Leaves are spirally scattered on long branches and clustered on short branches. The leaves are needle-shaped, hard, tapering, light green to blue-green. Dioecious, sparse and identical, with a single branch at the top. The cones are oval to oval-ovoid, and the seed scales and seeds are scattered at the same time after maturity, and the seeds have wings. The flowering period is from June 10 to June 1 1, and the flowering period of male cones is about10 days earlier than that of female cones. The cones matured in the second year (10).
Ecological habits originated in Himalayan region, widely distributed in Bhutan, Nepal, India and Afghanistan, and the vertical distribution height is 1300-3300m. The tropical climate from warm temperate zone to Central Asia with annual precipitation of 600- 1000 mm grows best in the middle and lower reaches of the Yangtze River in China. Strong cold resistance, large seedlings can withstand short-term low temperature of -25℃, but in hot and humid climate conditions, they often grow poorly. I prefer light, but my childhood is a little covered. Big trees need enough light, otherwise they will grow badly or wither. The requirements for soil are not strict, and both acidic soil and slightly alkaline soil can adapt. Deep, fertile and loose soil is most suitable for its growth, and it can also adapt to sticky loess and barren dry land. Drought resistance, water resistance and moisture resistance. Shallow roots and poor wind resistance. The resistance to sulfur dioxide is weak, and high concentration of sulfur dioxide in the air often leads to plant death, especially when new buds germinate in April-May.
Most cedars have the peculiar smell of males and females. In addition, due to the unexpected flowering period, the natural pollination effect is poor. In order to get full seeds, artificial pollination is needed.
Propagation and cultivation generally adopt sowing and cutting propagation. Sowing can be carried out in the middle and late March, and the sowing amount is 75 kg/hectare. You can also sow early to increase the disease resistance of seedlings. Choose sandy loam with good drainage and ventilation as seedbed. Soak the seeds in cold water for 1-2 days before sowing, and then dry them before sowing. After 3-5 days, the seeds began to germinate for about 1 month, and the germination rate reached 90%. Pay attention to shading at seedling stage to prevent the harm of Rhizoctonia solani and cutworms. Annual seedlings can reach 30-40 cm high and can be transplanted in the next spring. Cutting propagation can be carried out in spring and summer. Spring should be before March 20, and summer is best in late July. In spring, cutting off the annual thick branches of young mother trees and treating them with rooting powder or 500 mg/L NAA can promote rooting. Then insert it into sandy loam with good ventilation, water it fully, and build a double-layer shade shed for shade. In summer, semi-lignified branches should be selected as cuttings. In addition to strengthening shading, plastic film should be covered to keep humidity. Callus can be formed 30-50 days after transplanting. At this time, 0.2% urea and 0. 1% potassium dihydrogen phosphate solution can be used for external fertilization.
Breeding seedlings can be transplanted after 1-2 years in bed. Transplantation can be carried out in February-March. Plants need to carry earth balls and erect poles. The plant spacing is from 50 cm to 200 cm, and gradually increases. Topdressing for 2-3 times during the growth period generally does not require shaping and pruning, but only sparse dead branches and densely planted weak branches in the canopy. Botrytis cinerea can be controlled by spraying benadryl or zineb, and scale insects, moths and butterflies can be controlled by spraying omethoate and trichlorfon.