Methods for Pest and Disease Control in Cherry Trees During Winter Dormancy

Using manual and agricultural methods, clean the orchard, eliminate overwintering sources of pests and diseases, effectively eliminate harmful organisms, and reduce the overwintering population base.

1. Sweep up fallen leaves: Fallen leaves are one of the main overwintering sites for many pests and diseases. For example, the pathogens of cherry brown spot disease and black ring rot all overwinter on infested leaves, and pests such as the tortricid moth overwinter as pupae or adults hidden in infested leaves. Therefore, after cherry leaf fall is complete, thoroughly sweep up the fallen leaves, bury them or compost them directly, and eliminate the pests and diseases overwintering on the leaves, which can greatly reduce the pest and disease base for the following year.

2. Combine with pruning and cut off diseased and pest-infested branches: Winter pruning is an important technical measure in cherry tree management and is also an effective method of eliminating overwintering pests and diseases during dormancy. Reasonable pruning can regulate the tree's load, improve orchard ventilation and light conditions, promote healthy growth of the fruit trees, and enhance their ability to resist pests and diseases. At the same time, in combination with pruning, cut off branches infested by pests and diseases that overwinter on the branches, such as the tortricid moth, peach aphid, leaf-curling aphid, and red spider mite, and burn the pruned diseased and pest-infested branches in a centralized manner to eliminate the overwintering pests and diseases on them.

3. Deeply dig the tree basin: Many overwintering pests and diseases lurk in the soil beneath the tree canopy. Before the soil freezes, deeply dig the tree basin, which can directly kill a portion of the fruit-boring moths, pear lace bugs, pear star caterpillars, boat-shaped caterpillars, and hawthorn red spider mites (the winter-form female adult mites overwinter in soil crevices around the root crown, under fallen leaves, and among weeds) that overwinter in the soil. At the same time, by turning the soil, some pests can be exposed on the soil surface; these pests are either pecked and eaten by birds or frozen to death in the cold winter.

4. Scrape off cracked bark, rough bark, and disease tumors: The cracked bark and rough bark on the trunk are the main overwintering sites for pests and diseases. For example, hawthorn red spider mites (winter-form female adult mites), tortricid moths, pear fruit moths, and pear star caterpillars all overwinter under cracked and rough bark. Scraping off cracked bark and rough bark can eliminate most of the above pests. Scrape off crown gall disease tumors and gumming disease gum blocks. For crown gall disease, use 1% copper sulfate, 80% 402 antibacterial emulsifiable concentrate at 50 times dilution, or after scraping off the diseased spots, apply 40% asomate wettable powder at 30 times dilution to the wound. For gumming disease, use a mixture of 50% thiram 50 g + 50% sulfur suspension concentrate 250 g for application. This has a very good effect on reducing the sources of infection for the coming year.

5. Protect wounds and seal saw and pruning cuts. The wounds left on the tree by winter pruning are pathways for pathogen invasion and are also overwintering sites for some pests. You can use clear lacquer or tung oil mixed with an appropriate amount of lard, and apply it to protect the wounds and prevent pathogen invasion.