Bark beetles are known to attack trees already weakened by other environmental factors.

CNN: Global warming threatens forests, study says

The court heard the brothers picked a "discreet" location for the scene of their first attack, in trees by a stream.

BBC: Young brothers admit boys' attack

The report's numerous authors also attack claims that the presence of trees prevents catastrophic landslides.

ECONOMIST: Deforestation and floods

Seminars are being held to offer landowners and tree planters advice and guidance about how to deal with the fungal spores which attack young saplings and mature ash trees.

BBC: Ash dieback: More positive tests in Carmarthenshire

Officials had noticed that local trees seemed to be under attack, showing damage such as cracks, discoloration and tissue deterioration.

FORBES: Wi-Fi Might Not Kill Trees After All

Sitting now on lawns, amid well-tended flowerbeds and chattering picnickers, it is hard to imagine the British Army swarming onto this plain to attack the French, the smoke of gunfire forming a thick haze among the trees, the slashing of bayonets, and the screaming of the wounded.

BBC: Qu��bec's wood runners