Non-native trees reduce native diversity in eastern US

A new study reveals that non-native tree species are increasing in eastern North America, leading to a decline in native tree diversity. This is the largest study of its kind. Researchers analyzed over 5 million tree measurements from a 120-year-old USDA program, finding that the spread of introduced species has accelerated in the last two decades. Areas with these species show a decrease in native tree populations. The study highlights the negative impacts of introduced species, emphasizing the need for mitigation and prevention efforts. Researchers are creating risk maps to help focus conservation efforts.