In this regard, Jong Chol Ryong, head of the Forest Blights and Harmful Insects Institute under the Academy of Forest Science, told KCNA:

In recent years, the institute has developed various kinds of bio-insecticides suited to the country's conditions and supplied them to many units.

Microbe germicide gives no harmful effect on human body or ecological environment and it is used to combat wilt and other diseases occurring in saplings.

In particular, the Central Tree Nursery under the Ministry of Land and Environment Protection and other tree nurseries across the country raised the extermination rate up to 70 percent with this germicide.

Efforts have been also paid to wiping out forest blights and harmful insects with natural enemy insects. The institute keeps breeding bees of Trichogramma dendrolimi and supplies them to the parasitic bee production bases.

Besides, nicotine emulsion was introduced to exterminating larch caterpillars, plant lice, etc.