Phuong Son, a representative of Jasmine Tours, says the activity has been organized by the company since April.

The company handles around 2,000 guests a month, and each plants one tree, and more than 5,000 have been planted so far, he says.

The project began after tourists and drivers noticed bare hillsides along the Ha Giang Loop, where erosion is common during the rainy season.

A group of foreign tourists till the soil to plant trees in Ha Cho Hamlet in Ha Giang of Tuyen Quang Province in Vietnam's northern highlands. Photo courtesy of Jasmine Tours

"We hope this project helps restore degraded land, increase forest cover, and reduce erosion," Son says.