The Colorado River doesn’t flow like it used to. Massive concrete dams tame its historical flood patterns. Thirsty farms and cities siphon away more and more water. And climate change is supercharging ...

Giant dams built to conserve the Colorado River have nearly wiped out nearby native cottonwood trees, causing big ecosystem disruption. Tiny dams built to mimic those built by beavers could bring them ...

It seems fitting that Nebraska, which has chosen the cottonwood as its state tree, would have the largest one in the United States. The Nebraska Forest Service learned this week that a towering tree ...