The soil and climate here are very suitable for the growth of sweet potatoes. Li Dongling in Yanling County was once a barren mountain. Local farmers tried to grow all kinds of crops here, but none of them succeeded. Until one year, a farmer planted sweet potatoes here and unexpectedly found that the soil and climate here were very suitable for the growth of sweet potatoes. Since then, more and more farmers have started to grow sweet potatoes here, and Li Dongling has gradually been called "Sweet Potato Ridge".