Mycorrhizal Infection in Grasses of Kenyan Savanna

(1) Root samples of five grass species, distributed over four soil types, were collected from a savanna region in southern Kenya. (2) All samples, including those from seasonally flooded sites, had vesicular-arbuscular mycorrhizal infection. (3) In the main collection in November, near the start of the wet season, infection was lowest on a freely drained soil low in organic matter. This appears to have been due to a decline in mycorrhizas since the end of the previous wet season. (4) The speed of development of an effective mycorrhizal system early in the wet season may be important for savanna grasses.