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Recent satellite observations of the West African Sahel have shown an increase in vegetation greenness. However, many of these studies have little or no field validation to ascertain the actual environmental conditions on the ground. Here, we assess the condition of woody vegetation species in relation to land degradation processes and examine the conditions and patterns of their changes in the Nigeria-Niger border region in West Africa. Indigenous knowledge, a botanical survey, field observations and trend analyses were used to evaluate ecological changes in the area. A survey of 70 respondents which were selected using purposive sampling is presented i.e. 10 respondents each from seven villages, and focus group interviews were conducted to ascertain the condition of woody vegetation changes. The results show that despite the overall increase of vegetation greeness observed from remote sensing, the diversity and density of indigenous woody vegetation species is declining throughout the area. Nearly 80% of all the indigenous plant species of the region such as Borassus aethiopum, Ficus thonningii and Ficus thonningii have either completely disappeared or migrated southward where climatic conditions are more favourable. Therefore, the evidence suggests that land degradation is ongoing in the region and that local knowledge should be integrated in ecological resource management, especially at the local level, where locals rely on woody trees for food, income and fuelwood, so that plant species at risk of extinction can be preserved and where possible regenerated for conservation and sustainable use of the woody plant species in the region. (C) 2018 Published by Elsevier B.V.