Floristic composition and abundance of weeds in an oil palm plantation in Ghana

Abstract

The weed flora in an oil palm plantation situated in a semi-deciduous forest zone in Central Region of Ghana was assessed to identify the weeds and evaluate their abundance. The comprehensive stock of weeds obtained was analyzed to determine the relative abundance of taxa and life forms. One hundred and thirty-six weed species belonging to 33 dicot families, 3 monocot families and 8 families of Pteridophyta were identified. The weed families derived from seven subclasses; the most diverse of the dicots were the Rosidae and Asteridae. The monocots present were from the Commelinidae. Eight plant life forms were identified; the most diverse were the herbs, which consisted of 79 species and 56 genera; and the shrubs which consisted of 32 species and 26 genera. In terms of abundance and distribution, weeds of Poaceae and Asteraceae were found to be far more invasive. Chromolaena odorata, Aspillia africana and Melanthera scandens of the Asteraceae, Panicum maximum and Imperata cylindrica of the Poaceae and Mallotus oppositifolius of the Euphorbiaceae were widespread and problematic. The diversity of weed species was high in the oil palm plantation