Tweheyo has done research and applied work in forestry, wildlife, ecology, environment, socio-economic development, wetlands, agroforestry systems, land restoration, water quality assessment, climate change sciences, adaptation and mitigations; and food security. The most outstanding of this is the development and establishment of apple seedlings using neutral soils. Tweheyo has been invited to do short term work in other countries like Kenya, Madagascar, Rwanda, Tanzania, South Africa , Norway