Stinky landscape trees have spawned aggressive invaders in over 30 states: "Worse than murder hornets!"

Stinky but handsome and widely popular landscape trees have spawned aggressive invaders, creating thickets that overwhelm native plants and sport nasty four-inch spikes.

Bradford pears and 24 other ornamental trees were developed from Callery pears - a species brought to America a century ago to save ravaged pear orchards. Now, their invasive descendants have been reported in more than 30 states.

"Worse than murder hornets!" was the tongue-in-cheek title of a U.S. Department of Agriculture webinar in 2020 about Callery pears including the two dozen thornless ornamental varieties sold since the 1960s.