In pictures: Pakistan drug farming

1 of 8 Drug cultivation in the Tirah Valley, part of Pakistan's tribal area close to the Afghan border, is regarded traditionally as just another trade.

2 of 8 Pakistan says it is destroying poppy fields but this one was photographed in May. A farmer cuts a bulb and the secretion is collected before sunrise the next day.

3 of 8 A locally made tool used for cutting the poppy bulbs. It has many fine blades - the cuts must be made with care or the harvest can be lost.

4 of 8 A local opium trader says: "It is a trade. Nothing is bad or good in itself. The application of something makes it good or bad."

5 of 8 A farmer prepares his field for a cannabis harvest. He can get £60-£70 a year from a field of corn but 10 times more for cannabis.

6 of 8 Good quality cannabis seeds are sought to produce the best crops.

7 of 8 Cannabis has grown to plant form by May. The farmers then pray for rain and hope for a good harvest in October.

8 of 8 Cannabis traders operate in a wildly fluctuating market. The product can achieve up to $170 (£100) a kilogram depending on the time of year. Dry opium can make $670 (£400) a kilogram.