Landscaping under any tree can be challenging, thanks to the dense shade cast by the branches and the abundance of thick roots in the soil. But black walnut trees (Juglans nigra) seem to be in a ...

In 2010, Phoenix City Council approved an ambitious goal to plant enough trees to shade 25% of the city by 2030. Thirteen years later, city officials don't know how much progress they've made, if any.

Sixty miles east of Winslow, on the windswept plains of the Painted Desert, maroon-colored Triassic fossils recall a forest more than 200 million years old. Felled logs of the ancient conifer species ...