The willow tree is one of the main tree species in the Northern Park with its beautiful shape, leafing, flowering early, and green trees in early spring. The waterside greening in the garden landscape is most suitable for willow trees, such as the "Willow Wave Singing Warbler" in Hangzhou's West Lake, and the "Peach Creek Willow Bank" in Guiyang Huaxi. When in full bloom, the branches spread out in all directions, and the green stripes are flakes, which have high ornamental value and strong resistance to air pollution and dust, and are suitable for growing in urban gardens, especially in ponds or streams.
The breeze supports the willows and the posture is beautiful
This article mainly introduces the leaf-eating pests of the family Pyrophyllaceae that have a buliative and easy to destroy the landscape effect of willow trees.
Gluttony hazards of willow leaf nails
The Coleoptera leaf beetles that are harmed in willow trees are mainly the following: sweet potato leaf carapace, shield tumor thoracic leaf carapace, black frontal light leaf carapace, willow leaf carapace, green cryptocephalic leaf carapace, poplar leaf carapace, willow eighteen-ban leaf carapace, willow twenty spotted leaf carapace, willow round leaf carapace, wrinkled leaf carapace, light-backed saw-horn leaf carapace.
In May, it was found in many places in Beijing that the willow round leaf beetle endangered the willow leaves of the willow tree, and the serious harm would cause the willow tree to be bald and seriously damage the overall garden landscape effect of the willow tree.
It is a leaf-eating pest of the Coleoptera family , with a main distribution area of North China , East China , Central China , South China , Southwest China , and Henan. Generally, it mainly harms weeping willows and dry willows, and when the outbreak is severe, it will cause all the branches and leaves of willow trees to be eaten, leaving only the branches.
[Biological characteristics]
Adults are about 4 mm long and ovoid. The back is very arched, dark blue, metallic, body color varies greatly, and there are completely brownish yellow, elytra copper green or periphery, head, thorax, and ventral brownish red; The head is small, the leaves are wide and wide, and the carving points are fine; The dorsal plate of the anterior chest is wide and smooth; The engravings on the elytra are thick and deep; The shoulder blades are convex and there is a brown concave on the outside.
Adult willow leaf beetles cross tails
The eggs are orange-yellow and oval.edicipated.
The larvae are about 6 mm long in old age, flattened, grayish-yellow; There is a large brown spot on each side of the midline of the dorsal plate of the anterior chest, and there are large black-brown papillae on the lateral margins of the middle and posterior dorsal plates; There are 2 dark spots on the sub-dorsal line, arranged anteriorly and posteriorly; The 1st to 7th abdominal segments each have smaller black papillae and a yellow suction cup at the end of the abdomen.
The pupal is oval, yellow-brown, about 4 mm long, with 4 rows of dark spots on the back of the abdomen.
【Biological Cycle】
Three generations a year occur in Beijing, where adults overwinter in deciduous leaves, weeds and soil. In the spring, willow trees sting, mating, and laying eggs when they sprout. Adults have a suspended death. The egg stage is about 1 week. The larvae are infested in groups of leaves, and the leaves are networked at the site of the victim. The occurrence of this insect is very irregular, and adult and larval activity can be seen from spring to autumn.
【Prevention and control method】
1. Foliar spraying is carried out using Guoguang Gonger dilution 1000 times + Guoguang 1000 times or Guoguang Rick dilution 1000 times during the occurrence of adults and larvae.
2. Remove leaves, weeds and soil turning in winter to eliminate overwintering adults.