What was the impact of sharecropping on the south?

During what Era? Years? Sharecropping has had a HUGE impact on the southern economy for years?

Sharecropping has benefits and costs for both the owners and the tenant. It encourages the cropper to remain on the land, solving the harvest rush problem. At the same time, since the cropper pays in shares of his harvest, owners and croppers share the risks of harvests being large or small and of prices being high or low. Because tenants benefit from larger harvests, they have a push to work harder and invest in better methods than in a slave plantation system. So the impact was either good or bad depending on the crops harvested that season. 

Idon’t know wish i can