A Chinese banyan tree was among several trees that were recently cut down by the Municipal Affairs Bureau (IAM).
In a statement, the Bureau noted that the old trees, namely the Chinese banyan tree located at the Mong Há Hill Municipal Park, were cut down due to being infected with brown root rot disease, also known as ‘tree cancer.’
IAM said that the tree has been removed since “its roots and trunk have shown signs of severe decay.”
The Bureau explained that “tree removal measures must be taken when necessary if trees suffer from severe illness or endanger public safety as there is no fungicide capable of preventing and treating brown root rot disease,” adding that in addition to the removal of the tree, the services also adopt methods such as removing all infected roots, disinfecting the soil, and setting up physical separation barriers in order to stop or delay the spread of the disease in the affected area.
In Macau, brown root rot disease is more commonly found in Guia Hill and Mong Há Hill Municipal Parks.
According to IAM, sporadic cases have also been found in other parks, as well as in roadside trees.
The disease is considered common in Macau and is caused by the pathogenic fungus Phellinus noxius. The fungus corrodes the wood, causing it to become light, dry, spongy, white, and decayed.
The same fungus can also cause damage to the tissue responsible for the transportation of water and nutrients, causing the plant to lose its ability to absorb water and nutrients.
Since the base of the tree trunk and the roots decay first, trees lose the ability to support themselves and are at risk of collapse.
The disease can be spread through close contact with infected roots and tissue, posing a risk to other trees and plants growing in the surroundings of an infected tree.
The disease is slow to progress and there may be a few years between the onset of the infection and the death of the tree. As the leaves tend to remain green in color, the IAM says that it is difficult for those unfamiliar with the disease to spot an infected tree in the early stages.
