Readers discuss grassland conservation and a hummingbird flight trick

Conservation considerations

The online mapping tool Landscape Explorer uses historical and modern aerial images to show how the American West’s landscapes have changed over the last 70 years, Brianna Randall wrote in “Landscape Explorer transports you back to a more wild West” (SN: 12/2/23, p. 32).

Randall wrote that Landscape Explorer has helped conservationists in Montana prioritize where to remove invasive trees that have taken root in grasslands, which threaten local biodiversity and increase the risk of catastrophic wildfires. Given the climate crisis, reader Mark Granville wondered why conservationists would cut down trees that help remove carbon dioxide from the atmosphere.