1. There are black spots on poplar leaves sprayed with chemicals, which may be caused by anthracnose. It needs to be prevented in time, and the leaves will gradually turn yellow and rot, which will also affect the growth of willow trees. Dilute the mixture of sulfur and Bordeaux solution and spray it on the damaged leaves once every half month for 2 or 3 times continuously, and the leaves will gradually recover.
2. Pruning branches and leaves Poplar has dense branches and leaves and grows rapidly, so it needs pruning in time. After black spots appear on leaves, removing damaged leaves and withered old leaves can not only reduce the consumption of excess nutrients, but also effectively enhance air circulation, avoid the breeding of bacterial pests and effectively promote the sustainable growth of poplars.
3. Temperature control The suitable growth temperature of poplar is between 20℃ and 30℃. If the temperature is not suitable, black spots will appear on the leaves. In summer, the temperature rises, the environment is dry, the air is not circulating, and bacteria and pests breed in large quantities. Poplar trees need to be maintained in a ventilated place, sprinkled with water in the air and on the surface of leaves, and kept cool and moist.
4. Soil selection: Poplar must be developed. It is necessary to choose loose and fertile soil and add silt stones to enhance the air permeability of the soil. When poplar is ploughed in time, the soil will harden, the growth rate will slow down, and the leaves are prone to black spots. Effectively promote the absorption of poplar roots and do a good job of soil drainage in rainy season.