May is often the start of lawn-mowing season, but some cities are taking heed of bees' needs and asking homeowners to let clover, dandelions and other flowering plants grow in May.
The endangered California condor, the largest native North American bird, returned to soar the skies over the state's far northern coast redwood forests for the first time in more than a century.
With the climate warming rapidly, scientists are finding that cutting fossil fuels may not be enough. Carbon dioxide emissions may need to be vacuumed right out of the air.
Four U.S. states are still struggling with high rates of lead poisoning from soil, pipes and paint. It impacts thousands of people each year, especially low-income communities and families of color.
The countries share a border. Along the frontier, residents say a new barrier has disrupted everything from Arctic climate action and nuclear waste control to trade and cross-border sports leagues.
Texas closed most public oyster reefs for harvesting, dealing a blow to the fishing industry. "It's taken a big toll on me," says Johny Jurisich, whose family has worked in the business for decades.
The lawsuits contend that purchases of thousands of fossil fuel-powered delivery vehicles will cause environmental harm for decades to come. The Postal Service says it conducted a thorough review.