When botany professor Bharat Babu Shrestha visited Nepal's Chitwan National Park in 2013, feverfew — a flowering plant in the daisy family — was rare.
Today, large areas of the park's grasslands are covered in the invasive plant, said Shrestha, who teaches at Tribhuvan University on the outskirts of Kathmandu.
Nonnative plants have been spreading fast in Nepal's oldest national park in recent years — and part of the reason is rising temperatures as fossil fuel use heats up the planet, said the expert in "invasion ecology."