The 19 percent decrease in cultivation reported on Wednesday was mainly due to unfavorable weather conditions.
The annual survey, published by the United Nations Office on Drugs and Crime and Afghanistan’s Ministry of Counter Narcotics, showed 183,000 hectares (452,200 acres) in opium poppy cultivation in 2015, down from 224,000 hectares in 2014. Average opium yield per hectare was also down 36 percent.
The Taliban are heavily involved in poppy cultivation, as the plant can be processed into heroin. Opium production in Afghanistan had been on the rise since US occupation of the country began in 2001.
There has been a major counternarcotic effort in Afghanistan over the last 10 years, costing billions of dollars. Programs have encouraged farmers to produce other crops such as wheat, fruit and saffron instead of poppies.
“We did our best to make farmers understand how dangerous that is for Afghanistan and how harmful it could be for the future of our country,” said Zabiullah Daim, media adviser to Afghanistan’s counternarcotic minister.
Helmand is the major opium-cultivating province, accounting for some 86,400 hectares of production, 47 percent of the total.
Opium cultivation decreased in most of the main opium poppy-growing provinces, especially Nangarhar, Nimroz and Kandahar. But it rose by 117 percent in the province of Badghis and by 22 percent in Uruzgan.
The UN said the technology used to conduct crop monitoring and assessment between 2014 and 2015 had been refined, leading to greater accuracy of estimates. This may have had an impact on the extent of year-on-year changes, according to the UN.
In 2007, 92 percent of the non-pharmaceutical-grade opiates on the world market originated in Afghanistan. In addition to opiates, Afghanistan is also the largest producer of cannabis in the world.