See acacia-tree-can-boost-crops-and-more-across-africa for a story on how Acacia trees can boost crops - and more - across Africa.
In it, Nobel Peace Prize winner Wangari Maathai, founder of the Green Belt Movement in Kenya, says that the lack of extension services that tap into agroforestry science from research institutions and universities and then pass information to smallholders is a great disservice to the quest for food security in Africa.
The development and deployment of such extension services are a huge challenge that could/should be addressed under Education-for-All and Sustainable Development programmes (see for instance Bonn Declaration: ESD2009_BonnDeclaration )
The present failure-mode is collective and broad-based.
From the training/education perspective, addressing concrete cases in a sound architectural approach, leveraging new ICTs (internet, mobile communications, telecenters) (for a trial approach, see e-learning case ) can help securing conditions for repeatable success and virtuous spill-overs.
Considering the public private nature of the action theatre, also the approach of "Growing Inclusive Markets" seems a suitable option to accelerate the diffusion and embodying of knowledge (for details, see Growing Inclusive Markets ), in particularly so if entrepreneurial incentives can be combined with fit communal (forest) tenure rights (see figure 2 in the paper on the invisible map (of community tenure rights, by Barry and Meinzen-Dick pdf )