"Capitalism could revolutionize agriculture in Europe, but it could not do the same for Africa. In some districts, capitalism brought about technological backwardness in agriculture. On the reserves of Southern Africa, far too many Africans were crowded onto inadequate land, and were forced to engage in intensive farming, using techniques that were suitable only to shifting cultivation. In practice, that was a form of technical retrogression, because the land yielded less and less and became destroyed in the process. Wherever Africans were hampered in their use of their ancestral lands on a wide-ranging shifting basis, the same negative effect was to be found. Besides, some of the new cash crops like groundnuts and cotton were very demanding on the soil. In countries like Senegal, Niger, and Chad, which were already on the edge of the desert, the steady cultivation led to soil impoverishment and encroachment of the desert."