Soybean county estimates (2012 and 2013-2014) compiled by NASS give a definitive yield picture to aid in this determination. A summary of that information is shown in the below table.
|Location of and Yield (bu/acre) from Mississippi Harvested Soybean Acres, 2012-2014|
|North Delta (NASS District 10)|
South Delta (NASS District 40)
North Central (NASS District 20)
Northeast (NASS District 30)
East Central (NASS District 60)
Central (NASS District 50)
Southwest (NASS District 70)
South Central (NASS District 80)
Southeast (NASS District 90)
|**Included in other counties.***Included in other districts.|
The Delta counties (Districts 10 and 40) contained 71% (1,383,000 acres), 68% (1,353,000 acres), and 70% (1,548,000 acres) of the state’s soybean acres in 2012, 2013, and 2014, respectively.
The North Central and Central counties (Districts 20 and 50) contained 13% (251,200 acres), 13.5% (270,700 acres), and 12% (268,500 acres) of the state’s soybean acres in 2012, 2013, and 2014, respectively.
The Northeast and East Central counties (Districts 30 and 60) contained 13% (250,000 acres), 15% (299,000 acres), and 13% (290,000 acres) of the state’s soybean acres in 2012, 2013, and 2014, respectively.
South Mississippi counties (Districts 70, 80, and 90) contained less than 4% of the state’s soybean acres in all years.
All districts had higher yields in 2014 than in the previous two years, which resulted in the state average yield of 52 bu/acre, a new record.
It is obvious from the above data that average soybean yields are quite different among counties within a district; e.g. North Delta and North Central Districts. This is especially noteworthy in the East Central District in 2013 and 2014, where average yields in Noxubee County were considerably higher than average yields in the other counties in that district, and were more in line with the high average yields in the Delta counties.
There was considerable difference in average yields among the districts (e.g. South Delta vs. all other districts). Average yields from the North Central and Northeast District counties were the lowest or among the lowest in all three years. There is little doubt that rainfall patterns and irrigation played a significant role in these yield differences, but it logically can be assumed that doublecropping soybeans following wheat on a significant acreage in the two lowest-yielding districts may have been a contributing factor as well.
Average yields of soybeans in the South Delta counties were the highest among all NASS districts in all three years. All counties in this district produced average yields above 53 bu/acre. I suspect this district had the greatest irrigated acreage all years.
The above soybean yield differences among NASS districts can be subjectively analyzed, but objective analysis of these differences is impossible without a thorough knowledge of just what the enhancing or limiting factors in each respective county/district are. Identifying those factors and planning activities to address them should be a part of any soybean research and extension effort at representative sites within each district.
I encourage those who plan to initiate and conduct research and extension activities in Mississippi to consider the above data when planning those activities. This will ensure that limited time and resources will be allocated to addressing production problems in those areas of the state that are lagging behind in average yield, and to identifying the production practices that lead to high yields in the districts that continually produce those high yields. When you have information that supports either of the above objectives, it is incumbent upon you to transfer that information and technology to producers in those regions.
Two final points.
- It likely will be easier to raise yields in the lower-yielding counties if the factors that limit yield in those areas can be identified. This will involve applying all BMP’s that are proven to result in the highest yields if that is not already being done.
- The challenge to raising yields in the higher-yielding counties will be determining the incremental yield gains that can be achieved by micro-managing known BMP’s, probably on a field-by-field basis.
Composed by Larry G. Heatherly, Feb. 2015, email@example.com