We're cutting down our forests to cultivate the plants which give us nourishing food.

cultivate 是动词，来自拉丁语词根 cult-（耕作、培养）加上动词后缀 -ate。本义是"耕作、栽培"，引申为"培养、发展"的意思。在这里指通过耕作土地来种植作物。