Yield Response to Boron and Changes in Meh 1 Soil Boron over Time.

Research  was conducted on  a Staser silt loam  (Fine-Loamy Mixed, Active Thermic, Cumulic Hapludoll)  at the Springfield Research and Education Center in middle Tennessee.  Mehlich 1 boron (B) initially tested 0.4 mg/kg in the top 15 cm in 2009. Boron was applied each year with 4 replications of  a control plot and 3 rates of boron at  2.3, 4.5 and 9 kg/ha.  The site was  then cropped to bermuda grass hay for 3 years with no response to added boron. In 2012, Alfalfa was then cropped at the same rates of applied boron  each year for 3 years with no response to added boron. This current study started in 2015  evaluating boron in a corn, wheat, soybean row-crop rotation. The initial two years have shown no yield response  or apparent  reduction in yield to boron from all 3 row crops.

Soil test boron in the top 15 cm remained at reasonable soil test values, at all rates of applied B since 2009 (8 years) , In Sept. of 2016, an evaluation of boron throughout the  top 60 cm of each plot revealed increased boron in the rate plots over that found throughout the same  depth in the control plots. At the rates applied, soil boron enrichment to at least 60 cm occurred over the 8 year period.