AFGHANISTAN: Above-Average Wheat Production Outlook in 2010/11
Afghanistan is currently having its second consecutive successful wheat growing season, as plentiful autumn planting rains ensured the majority of the crop got off to a strong start. Overall grain growing conditions have been less favorable though than last year, when record crop area and yields resulted in a bumper harvest. Overall winter snowfall was substantially lower than last year, implying that total irrigation supply and irrigated crop yields will be reduced. In addition, well-above normal temperatures blanketed the major lowland wheat growing regions, causing heat stress and increased crop water demand. Satellite imagery of most of the country’s lowland irrigated cropping areas shows a marked decrease in crop vigor compared to last year, and indicates crop yield and production will be substantially lower. USDA is currently forecasting 2010/11 wheat production in Afghanistan at 3.7 million tons, 13 percent below last year’s record level but 18 percent above average.
Above normal autumn rainfall set the stage for a successful wheat planting campaign across the majority of the country. Crops were well established by early January, and showed signs of faster than normal development. Drier weather throughout January, however, caused considerable concern, as the nation’s mountain snowpack was at suboptimum levels. Seventy percent of the country’s wheat production relies on snowmelt for its irrigation supply. In years of low snowfall, wheat production declines precipitously. In early February 2010, a significant storm front moved through Afghanistan, replenishing the snowpack in the central Hindu Kush Mountains and reviving prospects for irrigated crop production. Subsequent heat waves, however, in February, March, and April caused rapid snow melt and depleted available irrigation supplies. Temperatures in lowland cropping regions ranged between 30-35 degrees Celsius for extended periods during the spring, causing heat stress on crops as they went through reproductive growth stages. The combination of excessive heat and less than optimum irrigation supply is expected to result in a widespread decline in irrigated crop yields this year.
Wheat crops are currently in early grainfill stages at lower elevations, whereas upland rainfed crops are in vegetative growth stage. Typically, upland wheat crops mature later than lowland crops, and go through moisture sensitive reproductive flowering growth stage from mid-May through June. Lowland crops in most of the country are showing less favorable development than last year, whereas upland crops are generally as good or better than last year. The main exceptions are non-irrigated rainfed crops in the north and northwest regions in the provinces of Herat, Badghis, Faryab, Jowzjan, and Balkh. Each of these provinces rainfed crops had less spring rainfall than last year, and were subjected to prolonged above normal spring temperatures. The national wheat harvest normally occurs from mid-May to mid-July, with crops at the higher elevations maturing the latest. One negative effect of the winter pattern of warmer than normal temperatures was that snow accumulation was significantly lower this year. This could pose problems for the majority of irrigated winter and summer crops which rely on snowmelt.
Favorable early rainfall conditions allowed wheat crops throughout Afghanistan to get well established before the onset of the coldest period of the winter. Mild seasonal temperatures during the winter allowed crops to continue to grow gradually, and to increase in overall vegetative density and vigor. The outbreak of unusually warm episodes from February through April was detrimental to wheat crop development, causing growth rates and water requirements to escalate. Satellite-derived vegetation index data in late April 2010, when most irrigated lowland crops are normally at peak development (coinciding with flowering growth stage) showed wheat development and vegetative vigor to be much reduced from last year in the majority of lowland irrigated growing areas. The general decline in crop development and intensity appears directly related to the stress incurred during successive spring heat waves and to reduced supply of both rainfall and irrigation. The NDVI change-detection map above illustrates the degree to which crop density has declined relative to last year’s bumper crop, and suggests that wheat yields and production will decline this year.
Vegetation index (NDVI) graphs are useful for gauging the growth, development, and production potential of agricultural crops. They are especially useful in years such as this in illustrating the wheat crops potential yield. From the two graphs above, which illustrate wheat crop development in Jowzjan and Faryab provinces (representing 14 percent of total wheat production) it is apparent that crop development is inferior to last year and as a result, potential yields are only slightly above the long-term average. In the case of Jowzjan (primarily irrigated), the crop yield outlook is reduced from last year, but still slightly above average. In Faryab (both irrigated and rainfed crops), crop development is well-below last year, with yield potential barely above the long-term average for the region.
A visual representation of regional vegetative crop development in both Jowzjan and Faryab is illustrated by the two sets of images below. Based on knowledge of the location and concentration of agricultural lands, satellite-derived vegetation index data (NDVI) clearly show that generalized grain crop conditions are worse than last year in key major producing lowland irrigated and rainfed areas. This assessment, when performed on a local and regional basis across the breadth of the country, revealed similarly unfavorable crop conditions compared to last year in the lowlands, with the exception of the northeast. The assessment also uncovered generally favorable growing conditions in most of the highland rainfed crop regions of the country, indicating that crop yields may match or exceed last years record levels. The upland rainfed regions generally account for 30 percent or less of total national wheat production. Stable to increased production in these areas this year are expected to partly offset declines in production in the lowlands, and keep Afghanistan’s national wheat production potential above-average.
Current USDA area and production estimates for grains and other agricultural commodities are available on IPAD's Agricultural Production page or at PSD Online.