Select the correct answer.
What connection can be made between the Asian longhorned beetle and the emerald ash borer?

A. Both are no longer considered the most threatening invasive species.
B. Both are invasive species that have infested trees across the United States.
C. Both are invasive species that affect aquatic plan communities in the United States.
D. Both are no longer considered a threat to trees in the United States.

adapted from Unwelcome Guests in Acadia
Source: The National Park System

Some non-native animal species have been around for many years and do not threaten native plants and wildlife. Others are invasive and pose serious threats to plants and animals in both aquatic and terrestrial environments. Park staff are on the lookout for three other invasive insect species that are not yet here but could seriously damage Acadia’s trees.

Asian longhorned beetle larvae tunnel into many species of deciduous trees, damaging and eventually killing them. The closest infestation has required the removal of more than 35,000 trees in a 110-square-mile area in and near Worcester, Massachusetts—nearly every deciduous tree in some neighborhoods.

The emerald ash borer, another exotic wood-boring beetle, has killed tens of millions of ash trees in 25 states. This beetle is unintentionally transported by people to new areas via firewood. To prevent the infestation from spreading to other areas, the USDA has established quarantines that prohibit the movement of ash materials and hardwood firewood out of infested areas.

Unlike the Asian longhorned beetle and emerald ash borer, which are relatively newcomers, the hemlock woolly adelgid is established in many eastern states. In the Blue Ridge Parkway and Shenandoah National Park, up to 80 percent of eastern hemlocks have died due to infestations, affecting trout streams and entire terrestrial and aquatic plant communities. Acadia’s eastern hemlocks are vulnerable to this insect, which is favored by a warming climate.