Bark beetle outbreaks drop threefold this year

Lithuania’s State Forest Service reported on Tuesday that bark beetle infestations have caused damage to roughly 52,000 cubic metres of spruce trees this year, nearly three times less than the 166,000 cubic metres recorded in the same period last year.

Specialists surveyed over 400,000 hectares of potentially vulnerable spruce forests to assess the impact. The agency noted that hot, dry weather creates favourable conditions for the bark beetle to reproduce, while drought-weakened spruce trees become more susceptible to attack. The beetle damages trees by burrowing under the bark, weakening them until they die.

Monitoring begins when temperatures reach around 10–13°C and continues until autumn. Last year, a state of emergency was declared in the forests of Kazlų Rūda, Rokiškis, Šalčininkai, Trakai, and Vilnius districts due to bark beetle outbreaks, but it was lifted in January as the spread declined.

The service also reported that another pest, the pine shoot beetle, has damaged 11.2 hectares of young pine plantations this year, affecting an average of 13% of the seedlings.

To protect forests, measures include digging trap pits, treating seedlings with insecticides, and setting up pheromone traps. The agency emphasised that damaged trees must be removed promptly after storms to prevent the spread of pests to healthy forests. Storms and strong winds have felled or broken about 21,400 cubic metres of various tree species this year, nearly 50% less than last year.