Rosewood is one of the most trafficked wild commodities on earth. When it's cut it bleeds a blood-red sap. Having exhausted stocks elsewhere, Chinese traders have turned to west Africa. We are in Senegal where it's illegal to fell or export a rosewood tree. And yet, we can reveal they are being logged and smuggled at an alarming rate - from Senegalese forests through to the port of neighbouring Gambia and all the way onto China. Umaru Fofana investigates trade in trafficked rosewood worth hundreds of millions of dollars.