Lucy Wanjiru is a Kenyan farmer and grows Miraa for a living. The plant, also known as Khat, makes farmers work harder or keeps busdrivers awake for longer, she says. The plant has traditionally been grown and chewed on the Horn of Africa peninsula for a long time. But Lucy Wanjiru insists that the Miraa from her region is the best.

About "My favorite"

With all the talk of endangered species, the value of biodiversity and the usefulness of ecosystems, we sometimes forget why plants and animals are really worth protecting: because we love them, or depend on them for our own wellbeing. People from all walks of life and in all parts of the world have a favorite species. The reasons are many - perhaps because it is beautiful, or fascinating, or it helps them secure a livelihood. Meet some of these people and their favorites in our series "My favorite."