In Chinua Achebe's Things Fall Apart, Achebe places emphasis on the importance of yams to Okonkwo's Igbo clan within Umuofia. Yams are the essential crop within Umuofia; the yam is a crucial staple in the Igbo diet. The number of yams a man successfully grows indicates his wealth and rank within the society. Additionally, the cultivation of yams is associated with masculinity: "Yam, the king of crops, was a man's crop" (23). Okonkwo takes great pride in his ability to grow this important crop, and uses his skills as a way to display his own manly prowess. Early in the novel, Okonkwo chastises Nwoye for the way that he handles yams, threatening to physically harm his son. After this threat, Achebe writes:

"Inwardly Okonkwo knew that the boys were still too young to understand fully the difficult art of preparing seed-yams. But he thought that one could not begin too early. Yam stood for manliness, and he who could feed his family on yams from one harvest to another was a very great man indeed" (33).

Yams are of such important to Okonkwo's tribe that there is a festival to celebrate the harvest of yams, The Feast of the New Yam:

"The Feast of the New Yam was held every year before the harvest began, to honor the earth goddess and the ancestral spirits of the clan.... The new year must begin with tasty, fresh yams and not the shriveled rand fibrous crop of the previous year" (36).

The yam is incredibly vital to the clan, and more specifically to the traditions of masculinity associated with the tuber. 

The yam is a central feature of the Igbo creation myth. The god Chukwu gives one to the first human family he creates and supplies them with seeds to grow more to feed themselves. As the world at the time is covered entirely by water, Chukwu instructs the first man to kill his eldest son and daughter and to plant the seeds upon their graves. The yam, like Chukwu, is a demanding master. Chinua Achebe calls it “the king of crops, a man’s crop.” It takes considerable toil to tend to yam crops, and men who do it successfully must continue to make sacrifices to ensure a good harvest. Their sacrifices are not usually as severe as the ones Chukwu demanded, but sometimes things fall apart.

Because yams are so difficult to grow, a man’s wealth can be measured in them. A bountiful harvest indicates a long, difficult, and ultimately successful season of hard work. It reflects well on the man’s character. If he is weak or lazy, he will have nothing to show for himself. He will not be able to support a family or take part in the upper levels of Igbo society. Leadership roles are reserved for men. Men who cannot toil, in war or in agriculture, are not considered to be men at all.

In Things Fall Apart, Okonkwo’s father isn’t able to support his family and has nothing to give his son as he enters adulthood. Okonkwo makes a deal with a wealthy community member and plants his first seed-yams as a sharecropper during a season of unprecedented weather, including flooding. He succeeds where more experienced farmers fail because, he feels, his will is uncommonly strong. His new beginning recalls the myth of Chukwu’s first man creating a new life out of a flooded world.