Researchers studied how three different shrub species stabilize soil on steep highway slopes in cold regions of China. They found that Amorpha fruticosa was most effective at strengthening soil because it develops extensive fungal networks and produces more of a special soil protein called GRSP. Interestingly, steep slopes made the GRSP less effective, so the fungal networks became more important. This research helps engineers and environmental managers choose the best plants to prevent slope erosion and landslides.