Q: Attached are photos of two weeping caraganas, purchased from two different local nurseries. Both are called the same, but they look very different. One is starting to show yellowing of leaves.

Farmers in China's Ningxia Hui Autonomous region have managed to halt the desertification of their land by planting "suzou grass squares" and Caragana trees. [Photo by Zekarias Woldemariam/China ...