41. Pastrana said 20, 000 families had agreed to cut down their own coca plants in exchange for aid. 42. Crack and powder cocaine both are derived from coca plants grown mostly in the Andean valleys of Peru and Bolivia. 43. Samper noted that Colombia last year destroyed 25, 402 hectares of illegal coca plants , used to make cocaine. 44. But the farmers argue the subsidies can't make up for lost revenue from the more lucrative coca plants . 45. Peru and Bolivia have reduced their coca leaves harvest, though they have not ended the cultivation of coca plants . 46. Hernan Ordonez looks over the rows of coca plants and the other young men feverishly pulling in the cocaine harvest. 47. At least 2, 000 police and soldiers defied coca farmers last week and began cutting down illegal coca plants . 48. U . S . coca leaf expert Francisco Alvarez showed McCaffrey a coca plant and explained how farmers reproduce coca plants. 49. U . S . coca leaf expert Francisco Alvarez showed McCaffrey a coca plant and explained how farmers reproduce coca plants . 50. He has called for the withdrawal of troops from the Chapare and for the forceful destruction of coca plants to end.