I have been going thru some data i have collected trying to find out why the corn crop was so good in our area in 2015. In the following table it compares the air and soil temperature in corn gdd's using a base temperature of 50 degrees F.
 In the charts i compared the soil temperatures using gdd's acumulated on daily basis.
 In both cases the corn was no-tilled into rye stubble.

(air and 2 inch soil temps corn gdd 2014 vs 2015.bmp)

(2 inch soil temp corn cumulative gdd 2014 2015 chart 1.bmp)

(2 inch soil temp corn cumulative gdd 2014 2015 chart 2.bmp)

(2 inch soil temp corn cumulative gdd 2014 2015 chart 3.bmp)

(2 inch soil temp corn cumulative gdd 2014 2015 chart 4.bmp)

(2 inch soil temp corn cumulative gdd 2014 2015 chart 5.bmp)

(harlans nqnf rye stubble 5 29 2014 004.jpg)

(us boys corn 5 29 2015.jpg)

air and 2 inch soil temps corn gdd 2014 vs 2015.bmp (2783KB - 337 downloads)

2 inch soil temp corn cumulative gdd 2014 2015 chart 1.bmp (637KB - 314 downloads)

2 inch soil temp corn cumulative gdd 2014 2015 chart 2.bmp (639KB - 324 downloads)

2 inch soil temp corn cumulative gdd 2014 2015 chart 3.bmp (632KB - 315 downloads)

2 inch soil temp corn cumulative gdd 2014 2015 chart 4.bmp (639KB - 312 downloads)

2 inch soil temp corn cumulative gdd 2014 2015 chart 5.bmp (399KB - 340 downloads)

harlans nqnf rye stubble 5 29 2014 004.jpg (140KB - 345 downloads)

us boys corn 5 29 2015.jpg (203KB - 327 downloads)