Most treatment methods are ineffective at treating the PSHB infestation. Soil drench, surfactants and canopy spray methods can have adverse impacts on the natural system in the surrounding area. This could leave potentially dangerous chemicals exposed on the surface, or in the soil, leaving possibilities for unintended exposure of animals or humans.
Tree injection - is the most ecologically friendly and direct way to treat an infected tree, but this method requires specialized equipment that may be economically or locally inaccessible to most landowners. Direct-injection methods use chemicals that may have adverse effects on tree health. Caution should be taken when using other chemicals, as overexposure might kill trees prematurely or be completely ineffective altogether.
Biologic Army - a combination of parasitic fungi and predatory bacteria that affects the protection of insect digestive systems.
Pest control - working on organic-molecular level: fatty acids in the product directly affects exoskeleton structure of insects on impact. This causes deterioration in the spiracle structure (along with other parts of the exoskeleton) and ultimately leads to death. Although not confirmed to combat PSHB effectively, natural and organic treatments are easily applied and have less risk associated in terms of environmental pollution, human exposure and adverse effects on tree health. These methods may assist in the treatment of PSHB but should not be used as the only method of control.
Removal - rather than attempting to treat an infested tree, best practice would be to remove any infested tree as soon as possible. Removal of infested trees should only be done by certified and competent service providers. Inadequate disposal of infested material may increase the rate of invasion as well as introduce the PSHB to novel areas. As such, when cutting down, the branches should be chipped into pieces smaller than 20mm. This kills almost 95% of all PSHB beetles. If possible, the material should then be burned in a closed off area as PSHB females will fly out from the infested material when temperatures increase. The easiest way to handle large pieces of infested material is to solarise; cover the material with thick plastic, tuck in the sides to retain moisture and heat, and leave it in the sun for 6-8 weeks before use/transport.
Trapping - Attempting to trap PSHB should only be done in areas already infected with PSHB. Setting traps for PSHB in areas previously unaffected could accelerate the rate of invasion by attracting travelling females further away from the original reproductive host tree. Traps should only be used when:
● Single trees, or isolated stands of trees, with historic, cultural or high economic value are at risk (Champion trees, heritage sites or botanical gardens)
● Presence of PSHB in a newly invaded area needs to be confirmed and sampled (should ideally be done by qualified arborists, entomologists or other scientists)
Traps can reduce the chances of a travelling female PSHB infesting trees near the trap, but no evidence is available in the South African context of it assisting in reducing infestation probability. In heavily invaded areas, traps can be utilised to limit the dispersal of females by luring and trapping them as they leave the reproductive host.