Africa in the Grip of Witchweed

After years of drought and famine, the rains seem to have returned to Africa. However, with the rains come the ideal conditions for striga, a parasitic weed of enormous destructive power. This witchweed damages food production in three ways. First, there is a direct loss in yield because of attack by the weed. Secondly, farmers lose by switching to other crops which are less susceptible but have lower yields. Last, farmers abandon land as a result of heavy infestation. The biology of witchweed, its destructive properties, and efforts to control it by chemical and biological means are considered.