A World Food Programme demonstration plot. On the left is maize treated with Kichawi Kill, an eco-friendly bioherbicide made by social enterprise Toothpick that tackles the parasitic weed striga. On the right is a maize farm that has not been treated, and has been devastated by striga. [WFP, Lisa Murray]
When Catherine Wanjala woke up in the morning and saw the little purple flowers in her maize field in western Kenya, it broke her heart.