The series Tasks for Vegetation Science is devoted to a variety of research aspects in vegetation science, pure as wellas applied. Of the applied problems one of the most pressing is to achieve better kwledge and improvement of the pasture vegetation in tropical and subtropical regions. As series editor I was impressed by the sheer volume of useful scientific information concerning pasture plants from East Africa collected during many years by Dr. Boonman and compiled in one manuscript. Dr. Boonman first came to East Africa in 1963 on an overland journey along the river Nile which took him from Alexandria in Egypt to Lake Victoria in Uganda and Kenya and back again. After a brief spell as a cotton agromist in the Sudan Gezira he joined the grassland research team at Kitale, Kenya in 1966. Improvement ofseed yield oftropical grasses was his principal interest which finally led him into the fieldof breeding grasses. Well-kwn varieties from his work include Boma & Elmba Rhodesgrass as wellas Clone 13Elephantgrass. In 1979he was recalled to The Netherlands to head a cooperative seedcompany involved in the breeding of grasses and cereals. The author has focused this study on one region, Eastern Africa.Global application of theories runs into conflicts too easily with local types of farming, if t with bare ecomics. Very few books can be found that describe existing practices and seek local answers by digging deep in the stacks of old, local reports.