Morning glory may be killing Vietnam's forests

Morning glory has many subspecies, most clearly distinguished by white, purple and yellow flower colors. Of which, the yellow-flowered morning glory has the scientific nameMerremia boisiana,is a harmful alien species. It is a vine, its stem diameter is up to 8-10 cm, the highest can be 20 cm.

M. boisiananative to the tropical climate of Hainan Island and the Zhuang Autonomous Region (Guangxi Province, China).There is currently no document confirming the time the morning glory plant appeared in Vietnam, but many experts believe that it was several decades ago, distributed from Lang Son to Da Nang.

The plant entered Vietnam in many ways, such as seeds drifting along water currents, through migratory birds, or people seeing beautiful flowers bringing them home to plant.

Before the 1990s, morning glory did not cause serious damage, so there was little research on it. Even because of a lack of awareness of the level of danger, many people planted it on the mountain slopes along the Ho Chi Minh - Truong Son route to prevent landslides.

In recent years, the morning glory has invaded and damaged the development of forests. Typically, in Da Nang, this species has attacked the Nam Hai Van special-use forest, and even the Ba Na - Nui Chua nature reserve at a very fast speed. From streams to forest edges, the morning glory covers pine forests, acacia forests...

At Phong Nha - Ke Bang National Park, an investigation by Mr. Vo Van Tri and colleagues (Park Management Board, 2012) showed that the yellow morning glory is distributed at an altitude of less than 300 m, over a large area, and is able to adapt to many different habitats such as rivers, streams, special-use forests, and production forests.

The plant is also found in Quang Nam, Bach Ma National Park, Nam Dong (Thua Thien Hue)... In the North, it is found in Sa Pa (Lao Cai), Lang Son, and Quang Ninh.

According to Dr. Dang Thi Phuong Lan, Institute of Environmental Agriculture, the growth rate of the yellow morning glory not only reduces biodiversity but also gradually kills forests, especially protective forests, special-use forests and conservation areas. This plant species is gradually becoming a difficult problem in forest management, development and protection in many localities.

With fast growth rate and good regeneration ability, in many places, yellow morning glory forms a thick layer, competing for nutrients with other species.

Morning glory often spreads when the forest canopy is broken by road construction, construction works... to expose bare land. They climb quickly, cover and "rob" the light of woody and herbaceous plants, causing plants under their canopy to die due to lack of light. The layer of dead plants creates a layer of dry leaves that can easily cause forest fires.

Quang Binh province recently approved a pilot plan to eradicate the yellow morning glory plant due to its harm to the ecosystem and biodiversity of Phong Nha - Ke Bang National Park.