The investigation of weed spectrum in cassava fields was carried out in Derived savanna agro-ecology (Ido Local Government Area) of southern Nigeria in 2017. Thirteen (13) cassava farms were surveyed. Coordinate points, elevation of the investigation sites and mapping were conducted with Geographic information system (GIS). Weed flora composition of each location was studied by sampling randomly using ’M’ pattern of quadrat placement and average from the samples was recorded. Results showed that thirty-six (36) weed species cutting across twenty-one (21) families were identified. This showed the richness and dominance of weed flora identified in the agro-ecology. Tridax procumbens, Talinum fruticosum, Euphorbia heterophylla, Chromolaena odorata and Ageratum conyzoides were the most frequent weed species and evidently showed their broader environmental tolerance. Weediness in cassava fields ranged from 4.67/10 to 8.33/10 across locations. Cultural practices and location might have influenced the weediness and weed flora composition.
Keywords: Derived Savanna, Geographic information System (GIS), Weed Flora Composition, Weediness, cassava
