Multiple agencies and organizations throughout the range of eastern hemlock are responding to the crisis with a multi-pronged, integrated approach. None are a stand-alone solution, and instead work together to form a comprehensive plan for hemlock conservation. These methods are:
- Chemical control: This is a short-term, but sure-fire way to protect an individual tree. Hemlocks can be treated with a systemic chemical insecticide that spreads through the whole tree and lasts for 5-7 years. For more information, see our page titled Chemical Treatment under the Solutions tab.
- Biological control: This is the effort to establish a natural predator/prey balance that will keep adelgid populations at a level that hemlocks can tolerate. The most widely used species is the Laricobius nigrinus beetle, which has been well established in some areas that HWA has spread, particularly in Western North Carolina. Other beetle and fly species have also been approved as biocontrols for HWA. However, it is still too early to rely on these predators to keep HWA populations in check. For more information, see our page titled Biological Controls under the Solutions tab.
- Silviculture: This consists of programs working to determine forest management practices that can positively impact the health of hemlocks in the face of HWA, for example, how to manipulate forest structure to provide the best growing conditions that support hemlocks to withstand HWA . For more information, see our page titled Silvicultural Strategies under the Solutions tab.
- Genetic: These efforts include breeding native hemlocks that are resistant to HWA, and work to preserve genetic diversity for reforestation. For more information, see our page titled Genetic Research under the Solutions tab.