"If you try to grow other crops here they will fail," says Ahmed, surrounded by lush green fields of cannabis, the illegal plant he and thousands of other poor farmers in Morocco’s Rif Mountains depend on. The country’s most notorious export has been cultivated in the rebellious northern region for centuries, where the climate for growing cannabis, or "kif", is considered ideal above an altitude of 1,200 metres. "Kif is the only crop that can support my family, even though it’s not enough, because at the end of the year we need credit."