China Winter Wheat Update - April 2006

China’s 2006/07 winter wheat crop is progressing normally.  It is now in the jointing stage in the Yellow River basin and in the boot/flowering stage in the southern part of the North China Plain.  Temperatures have been generally warmer than normal since January, which caused the crops to emerge from dormancy ahead of schedule and develop rapidly in early spring. 

Favorable Rain in the Southern Plains
The four provinces in the central and southern plains (Henan, Anhui, Jiangsu, and Hubei) account for about 42 percent of total wheat production.  Temperatures were very mild during March and the first 10 days of April, averaging more than 5 °C above normal and reaching into the upper-twenties Celsius in many locations. Moderate to heavy showers from February through early April have maintained adequate to abundant soil moisture for crop development. Satellite imagery shows the wheat crop in the central and southern plains appears to be in good condition and vegetative index data (SPOT-NDVI) indicates that vegetative growth is better than average. 

Drier in the North, More Rain Needed
The wheat situation is not quite as favorable in the Yellow River basin (Hebei, Shandong, Shanxi, Shaaxni, Beijing, and Tianjin), where a minor drought is occurring.  This region accounts for about 38 percent of total wheat production.  A combination of below-normal precipitation and above-normal temperatures in February and March caused soil moisture to drop below optimal levels, and SPOT-NDVI values as of April 10 were below average in the driest locations. 

Scattered showers in the first 10 days of April brought some relief to the Yellow River basin, particularly to Shandong, Shaanxi, and northern Hebei provinces, but total precipitation since January 1 remains below normal and soil moisture has continued to drop. 

April Weather – Turned Windy and Cool
The weather changed dramatically during the week of April 9-15, when a strong cold front moved into eastern China from the northwest.  Most of the country saw temperatures drop by 8 to 16 °C, and scattered frost was reported in northern latitudes and higher elevations.  The cold front was accompanied by a serious sandstorm, one in a series of sandstorms that have hit northern China this year (some extending as far east as South Korea).  The front triggered a few showers in the Yellow River basin but caused locally heavy rain in central China, where soils were already wet.  The sharply-colder temperatures (minimum temperatures below 5 °C in most locations) did not drop low enough to damage winter wheat but may have had an adverse affect on the reproductive winter rapeseed crop, which is more sensitive to temperatures extremes. 

Extended Forecast – Warmer and Drier
The extended forecast (through April 21) calls for gradually warmer temperatures and sunny skies over most winter wheat areas.  Heading/filling normally takes place from April 20 to May 10 on the North China Plain (earlier in the south, later in the north).  Additional showers will be needed over the next 4 weeks to provide and maintain adequate soil moisture for normal crop development, especially in the Yellow River basin.  Harvesting will begin in May and peak during the first two weeks of June.  

The first USDA area and production estimates for the 2006/07 wheat crop will be published on May 12, 2006.

Links:

PECAD's Crop Explorer site (close this window and navigate to Crop Explorer)

MODIS Image Gallery (from the Crop Explorer Home page click the MODIS Image Gallery link)

Current USDA area and production estimates for grains and other agricultural commodities are available on PECAD's Agricultural Production page or at PSD Online.