Individual study: Combining napier grass with leguminous shrubs in contour hedgerows controls soil erosion without competing with crops
Mutegi J.K., Mugendi D.N., Verchot L.V. & Kung'u J.B. (2008) Combining napier grass with leguminous shrubs in contour hedgerows controls soil erosion without competing with crops. Agroforestry Systems, 74, 37-49
This study is summarised as evidence for the intervention(s) shown on the right. The icon shows which synopsis it is relevant to.
Plant new hedges
A randomized, controlled, replicated experiment in 2001-2003 on clay soil in Kenya (Mutegi et al. 2008) found less soil was lost from slopes with Napier grass Pennisetum purpureum barriers (14.9 t/ha) than with combination tree/Napier hedges (calliandra 19.2 and leucaena 16.2 t/ha), tree hedges alone (calliandra 25.3, leucaena 27.8 t/ha), or control plots (61.9 t/ha). Inorganic nitrogen was higher in tree hedge plots (33.1 and 30.8 (NH4 + NO3) kg/ha) compared to Napier barrier or control plots. Tree and combination hedges had higher maize Zea mays yield (2.6-2.9 t/ha) than Napier (1.5 t/ha) and control plots (2.2 t/ha). On 33 farms, hedges/barriers of calliandra Calliandra calothyrsus (tree), leucaena Leucaene trichandra (tree) or Napier grass, and combinations of the tree species with Napier grass were established, on slopes exceeding 5%. Control plots had no hedges. Plots were 10 m long stretches of hedge. Soils were sampled 20 months into the experiment; soil fertility and loss, and maize Zea mays crop yield were measured.