The correct answers are C) They used a creative method to maintain the fertility of the land and D) They cultivated the “three sisters” crops of corn, beans, and squash.
The two agricultural contributions that are common to both Northeast Woodland Indians and Southeast Indians are the following: They used a creative method to maintain the fertility of the land and they cultivated the “three sisters” crops of corn, beans, and squash.
The term "three sisters" in agriculture refers to the most important crops in the agriculture fields of some Native American tribes such as the Northeast Woodland Indians and Southeast Indians. The crops were corn, beans, and squash. The Native American Indians used a special agriculture technique called companion planting, that was the planting of different crops close to each other. So squash, corn, and beans were planted in proximity to each other.
