A definition of the concept as found in the novel:
The feast of the new yam is a ceremony that gives thanks to the goddess Ani, the goddess of fertility. She is also the judge of morality and conduct. New Yam, which is the staple food of the region, could not be eaten before this event. All yams from the previous year were thrown away and all yam utensils were cleaned. Everyone is happy and celebrates together.
A summary of a contemporary article that deals with the concept:
This article talks about the feast of the new yam in modern Ghana and Nigeria. The article specified that the celebration occurred in mid to late August, at the end of the rainy season. In modern times, at this festival, people bring yams for all to share. Aside from a feast of yams, people participate in cultural dances and masquerades. Today it is still a symbol of togetherness and community. There have been basically no changes to the way it is celebrated and it is still perceived positively, like it was back then.
Daniels, Ugo. "Iwa Ji Ofu (New Yam Festival) in Igboland!" AfricanLoft. African Loft, 11 July 2007. Web. 14 Apr. 2011.
New Yam Festival. 2011. Photograph. Enggods, Nigeria. Enggods. Sociologist, 2011. Web. 14 Apr. 2011.