The Cancer of Pine Trees: What Is Pine Wilt Disease? Its Harm to Humans and Control Options

There are more than eighty species of pine trees in the world, not only numerous in kind but also widespread in distribution, yet they are prone to an epidemic disease called the pine wood nematode.So do you know what pine wilt disease is? Is it harmful to humans? How is it controlled? What options are there? According to information from the Aphelenchoididae family, pine wilt disease is also known as pine tree wilt disease. It is a devastating epidemic disease of pine trees. In China, the Japanese pine sawyer beetle is its main vector insect. Its pathogenicity is strong, and host trees die quickly; it spreads fast and often catches people off guard; once it occurs, it is difficult to manage.

Is the pine wood nematode harmful to humans?

The main hosts of pine wilt disease are plants of the genus Pinus. In China it mainly occurs on Japanese black pine, Japanese red pine, and Masson pine. In seedling inoculation tests, loblolly pine, maritime pine, ponderosa pine, Yunnan pine, Himalayan pine, Korean pine, and Scots pine can also be infected, but mass mortality has not yet occurred in nature. So at present it is not harmful to humans.

How is pine wilt disease controlled?

The control of pine wilt disease mainly relies on transforming forest stands and clearing dead and diseased trees, while some chemical and biological means are also used to control the Japanese pine sawyer beetle. The main control methods are:

1. Clear-cut heavily diseased pine forests and isolated diseased pine trees, and use methods such as fumigation, heat treatment or chipping to kill the Japanese pine sawyer beetles in the diseased wood, so as to prevent the beetles from emerging and causing the spread of the epidemic.

2. Thin out dead and diseased trees in diseased pine forests, and use methods such as fumigation, heat treatment or chipping on diseased wood, diseased branches and root stumps to kill the Japanese pine sawyer beetles and prevent the spread of the epidemic.

3. For key protection areas, clear-cut the surrounding pine forests to establish control isolation belts.

4. Implement quarantine blockade in outbreak areas, strictly prohibit the transport of untreated diseased wood and the like to areas where the disease has not occurred, and prevent the spread of the epidemic.

5. During the emergence period of the Japanese pine sawyer beetle, spray pesticides to kill adults or set trap logs to trap and kill adults.

6. Spray chemical pesticides, release Sclerodermus wasps, or apply Beauveria bassiana and other methods to control Japanese pine sawyer beetle larvae.

What options are there for controlling the pine wood nematode?

The initial onset of pine wilt disease in forests generally occurs from the end of May to early June, and July and August are the peak period of the disease. So prevention can be done in advance:

1. Do a good job of quarantine blockade; this is an important means of preventing the introduction or long-distance spread of pine wilt disease;

2. Do good monitoring work, discover early and treat early, carry out control when the outbreak area is small and the degree of damage is light, and eliminate pine wilt disease in the bud;

3. Promptly and thoroughly clean up dead and diseased trees; before the vector insects emerge, clean up all dead and diseased trees completely, and the trunk wood, branches and root stumps of diseased trees must all be cleaned up and subjected to disinfestation treatment to kill the nematodes and vector insects within them and prevent further spread and damage.