Spruce bark beetle

Spruce bark beetle [Dendroctonusmicans (Kugelann)] belongs to the family Coleoptera, which is mainly distributed in Austria, Belgium, Czechoslovakia, Slovakia, Denmark, Finland, France and other countries. Some species of spruce, pine, fir, European larch and Douglas pine are also occasionally damaged in China.

The damage is characterized by adults and larvae. When the damage is rampant, it can infringe on healthy trees, seriously destroy the transport function of trees, and lead to tree weakness and even death.

The morphological characteristics are unknown

The occurrence regularity belongs to drill borer and secondary pests. One generation a year in the Makehe forest region of Qinghai Province, overwintering as adults or larvae under the bark of the killed trees. The period from the end of April to the middle of May is the initial period (adult flying period), the peak period of damage is from June to July, and the end of damage is the middle of August. In general, it is harmful to weak and withered trees, and when it is rampant, it can infringe on healthy trees.

Prevention and cure method

(1) strengthen quarantine to prevent the spread of seedlings and timber.

(2) strengthen the management of forest area.

① builds mixed forest, strengthens tending, enhances tree potential and reduces damage.

② should pay attention to the hygiene of forest areas, cut down the damaged trees and wind-broken trees, peel the roots in time, and burn them in time.

③ in the first and middle of April and May, before the adults fly, make use of the habit that pests like to spawn and reproduce on newly felled logs, and make bait trees from the tops of felled and dying trees and spare branches for tending and pruning. The bait wood was 1.5-2 m long, 3-5 roots and 1 group, padded with wood pad, 2-4 groups per mu, placed in the forest glade to attract adults to come to lay eggs. Peel the bait wood before the pests on the bait wood are feathered. The first peeling was made around June 10, and the peeling was concentrated out of the forest for timely treatment, and the new bait wood was replaced, and the second peeling treatment was completed before the middle of August.

(3) protect and utilize natural enemies such as woodpeckers.

(4) Pesticide control.

① trunk wormhole injection. Use 40% omethoate EC 100 times or 25% cypermethrin 50 times solution on the trunk of mildly damaged trees with syringes for wormhole injection, each hole injection dose of 5mL.

② spray control. During the period from April 20 to May 10, the trees and felling areas were sprayed with 1000 times of 40% omethoate EC or 25% cypermethrin, with an efficacy period of 3 times every 7 days.

Commonly used agents omethoate, cypermethrin,.