Soil erosion critically threatens agricultural sustainability in the Ethiopian highlands, particularly in Tigray. While bench terraces are widely implemented to combat this, their stability is compromised by vulnerable terrace risers. This study evaluated the performance of three grass species, namely, Rhodes (Chloris gayana), Vetiver (Chrysopogon zizanioides), and Wazwazo (Festuca roemeri) for biologically stabilizing bench terraces in Kola Tembien, Tigray, compared to a bare control. A Randomized Complete Block Design was used over two years (2019-2020) to assess growth parameters and soil loss. Results showed that Wazwazo had the highest tiller production, while Rhodes excelled in height, ground cover, root diameter, and biomass. Vetiver developed long roots comparable to Rhodes. Soil loss data revealed significant deposition under Rhodes (19.5 t/ha) and Vetiver (22.1 t/ha), stability with Wazwazo (0.0 t/ha), and significant erosion in the control (-16.9 t/ha). The study concludes that Rhodes grass is optimal for overall surface protection and fodder production, whereas Vetiver is best for deep structural reinforcement. Integrating suitable grasses significantly enhances terrace stability and reduces soil loss, offering a sustainable bioengineering solution for land management in erosion-prone landscapes.
