Disease and pest prevention
Pine seedling wilt disease
This disease occurs on 1-2 year old seedlings and also on 3-year old seedlings, but the annual incidence rate is very high. The symptoms of the disease vary with the growth time of the seedlings, generally showing the following four types: rotten shoot type, sudden fall type, stem and leaf rot type, and root rot type. The main pathogens causing seedling wilt disease are Fusarium oxysporum and Fusarium oxysporum. Generally speaking, when the soil is wet and low temperature, there are more filamentous fungi and dry soil. When the temperature is high, there are more Fusarium species. After the seedlings are damaged, they will develop symptoms within a few hours, so the infection is rapid. When the disease occurs after emergence, medication should be taken to prevent it: 30% Suhua 911 powder, with a dosage of 0.75 kilograms per acre as medicinal soil, scattered on the seedbed surface, or 720 milliliters of 30% Suhua 911 emulsion per acre with 250-500 kilograms of water, or 1:5000 times the dosage of Xinjier Mie. After 10-30 minutes of each application, spray clean water once to wash off the liquid on the leaves and avoid pesticide damage.
Chinese pine cone borer
In Zhanggutai area, there is one generation per year, and in May each year, overwintering larvae begin to break through the net. Most of them first enter the male inflorescence, and then enter the tender shoots and 2-year-old cones.
Chemical prevention: During the period of larval transfer, spray 40% dimethoate emulsion at 400 times dilution, 50% dichlorvos emulsion at 100 times dilution, 90% crystal dichlorvos emulsion at 300 times dilution, 80% dichlorvos emulsion at 1500 times dilution, or 20% vegetable and fruit phosphorus emulsion at 500 times dilution. After the emergence of adult insects, spray a 6% wettable hexachlorocyclohexane 200 fold solution every 7 days. In addition, red eye wasps can also be released during the spawning period, with around 150000 bees per hectare.
Pine stem borer
In the Zhanggutai area, there are two generations per year, with larvae of different ages overwintering in the adult path inside the treetops, and a few larvae overwintering under the trunk skin. The treatment method is the same as that of the pine nut borer.
Pine pit cutting bark beetle
Camphor pine, Pinus tabulaeformis, and others are all affected by it. The main harm is to the pine shoots and healthy trunk base, and diseased, dead, wind fallen, and wind broken trees are more severely affected. In addition to maintaining forest hygiene, the treatment method is to spray 666 powder.
Larch caterpillar

Harm to coniferous trees occurs once a year in the Zhanggutai area, starting around mid April each year. The treatment method is to do a good job in pest monitoring and reporting, while spraying pine caterpillar bacteria during the leaf feeding stage of larvae and using black light lamps to lure and kill during the adult stage. In addition, tying poisonous ropes to each mature tree is also a good way to treat pine caterpillars.