Air pollution from farms, diesel engines and factories is leaving trees malnourished by killing off the fungi that feed them nutrients, and "alarming" levels of disease in British trees. The researchers studied 40,000 roots from 13,000 soil samples at 137 forest sites

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Air pollution from farms, diesel engines and factories is leaving trees malnourished by killing off the fungi that feed them nutrients, and "alarming" levels of disease in British trees. The researchers studied 40,000 roots from 13,000 soil samples at 137 forest sites