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Bark beetles worry scientists as they hack through Swiss trees

Source: Xinhua| 2018-03-10 03:43:24|Editor: Chengcheng
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GENEVA, March 9 (Xinhua) -- Scientists are sounding the alarm after the bark beetle damaged 320,000 cubic meters of spruce in 2017 -- three to four times more than in 2008-2012, the Swiss government said Friday in a statement.

Switzerland's Federal Institute for Forest, Snow and Landscape Research (WSL) said the rise in damage caused to the ecologically-important spruce in 2017 is "worrying".

Storms, heavy snow and the hot summer weather laid further stress on the spruce, leaving them more susceptible to attack by pest species, which for breeding like weak trees or those that have not-long been dead, the WSL said.

"Even if there are some regions which have little beetle damage, we can no longer say that the situation has calmed down," experts were cited in the statement as saying.

The WSL expects an increase in the beetle population this year.

Winter storms, such as an especially damaging one called Burglind earlier this year also damaged the spruce population.

WSL experts recommend removing damaged and beetle-affected trees as soon as possible to limit the spread of the bark beetle.

Spruce trees make up around a third of the growing stock in Switzerland.

The spruce is the most important timber tree in the country and spruce forests often have a protective function in the mountains, says the WSL.

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