Behind the blossoming flowers and fields of fruit in the U.S. lurks a hungry threat that has crawled and eaten its way through much of the country. Sometimes, the menace infiltrates these places on the backs of unsuspecting hikers and travelers.
Almost always, the damage it wreaks comes at a high cost.
As summer approaches, swarms of invasive species—which the National Wildlife Federation refers to as "one of the leading threats to native wildlife"—are on a rampage. These organisms attack not just gardens, but also agriculture and the environment, costing the United States about $120 billion each year in damages, according to the Animal and Plant Health Inspection Service (APHIS), a division of the United States Department of Agriculture (USDA).
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"They are a serious threat to our economy," says APHIS spokeswoman Abbey Powell. "Federal and state authorities are tirelessly working together to stop the spread of invasive pests."
Of greatest concern to the government are a group of non-native ants, beetles, moths and flies, and one giant slug. APHIS has identified 18 of these pests that it believes pose the greatest threats to America's crops, plants and trees, and which inflict damage on a range of businesses, from farmers and citrus growers to the lumber industry.