WUHAN, July 28 (Xinhua) -- Walking through the knee-high grass, construction worker Hua Shankui bent down, pulled up a tuft of grass, and closely looked at the roots.

Having worked on building sites for over 20 years, Hua, 59, had never imagined he'd become an "expert" on planting grass. But this was exactly what happened at a site he's working on in Wuhan, central China's Hubei Province.

The 18-hectare construction site of the Huashan section of Wuhan metro line 19 is situated near a verdant ecological reserve. Construction workers knew well that efforts had to be made to ensure that the local environment would not be compromised, said Wang Ran, a member of staff at Wuhan Metro Group.

To reduce pollution, using dust nets to cover bare soil is a normal practice on construction sites. However, a decision was made at the Huashan site to plant grass on the soil, a more eco-friendly method.

When Hua was assigned the task of leading a grass-planting team, he knew nothing about horticulture. The first question facing the team was what kind of grass they should plant.

Hua turned to local gardeners, who recommended carpet grass, a species commonly planted in urban landscaping.

However, months after planting the grass, few seeds of carpet grass grew roots as the soil at the site contains too much gravel.

The team thought of improving the soil by picking out the gravel or covering it with straws to preserve moisture. They gave up on both methods as neither proved effective on the soil of eight hectares.

"Since the soil quality cannot be changed, I tried different varieties of grass. I believe I would eventually find the right one," said Hua.

After repeated experiments on a small piece of land, Hua found rye grass to be the right species for the Huashan construction site. The grass grows on almost all types of soil, sprouts in a week after seeding, and has proved to be hard to kill.

Hua and his colleagues started to plant rye grass in April 2021. They closely observed the weather, sowing seeds when the rainfall was just right.

Hard work paid off. Four months later, the piece of brown soil was covered in lush green grass, adding life to the construction site whilst cleaning the air.

One summer's day, looking down from a hilltop at the grassland he personally cultivated, "Look at the grass! It's so glossy and green." Hua commented as he could hardly contain his excitement.

According to Wang, dust nets are prone to damage from rain and sunshine. They also have to be replaced every two weeks, which costs about 200,000 yuan (about 29,669 U.S. dollars) each time.

Moreover, dust nets can be blown away on windy days, which could pose a danger to the cables of an adjacent railway network.

"Planting grass cost us 100,000 yuan, and once it's planted it lasts forever," said Wang.

Huang Chaojie, who's in charge of the Huashan site project, said Hua and his team's grass-planting experience can be introduced to more construction sites in Wuhan. "Hua should be praised for his dedication and research achievement," he noted.