It happened wasn’t losing the forest only a bad thing. According to the theory of self-destruction, the massive deforestation loosened the topsoil, which blew into the ocean, depleting the ground of nutrients and causing food shortages. However, ongoing research suggests that erosion was not the problem people have assumed.
What is apparent on the ground is the large number of rock gardens that cover much of the island’s interior, in which crops such as taro, yams and bananas were grown. These take several forms, from windbreaks made of large lava rock boulders to piles of smaller rocks mixed with earth that would have acted as so-called “lithic mulches” to keep moisture in the soil. Lipo and Hunt suggest that, given Easter Island’s poor soils and relatively low rainfall – which struggles to top 1500 millimetres a year – it actually made sense to get rid of the forest to make way for these gardens, and to extend agriculture across a greater range of soils and levels of rainfall.