Botanists may have worked out why pine trees suddenly died across China in the 1970s

Chinese botanists say they may have an explanation for a mass die-off of plantation pine trees across the country that has baffled scientists for 50 years – it could be all in the genes.

The Pinus armandii, or Mount Hua pine, is a species native to China, and can survive in harsh conditions such as mountain cliffs. The white pine is also a symbol of long life in Chinese culture – the Taoist God of Longevity is almost always seen in paintings with a Mount Hua pine in the background.

But in the 1970s, there was a large-scale die-off of the pines in reforested areas across many provinces, and the cause has never been found.

Now, scientists at the Kunming Institute of Botany in Yunnan province say they might have the answer. Led by botanist Liu Jie, the team collected samples from pine-growing regions across China to build the country’s largest database of information on the pine species.

Through genetic analysis, they found the species has three lineages – and these differences in genes mean they are not suited to the same conditions.

That explained why the trees planted during the reforestation campaign did not survive – they were not planted in their natural habitat, the scientists said in a paper published in the peer-reviewed journal Evolutionary Applications last month.