Comparison of Split Foliar Applications on Soybeans

  • 0
  • August 14, 2015
Experiment Info

Planted: 6/2/2011
Variety: Stine 1932
Population: 150,000
Plot Size: 15′ x 300′
Replications: 4
Previous Crop: corn
Foliar V3: 7/6/2011
Foliar R1: 7/12/2011
Foliar R3: 8/1/2011
Harvested: 10/11/2011

Soil Test Values (ppm)

 pH: 6.8
CEC: 8.0
%OM: 1.8
P1: 46
K: 70
S: 8
%K: 2.2
%Mg: 19.1
%Ca 77.4
%H: 0
%Na: 1.3
Zn: 1.8
Mn: 8
B: 0.7

Objective:

Agro-Culture Liquid Fertilizers has two main foliar program options for soybeans. Depending on soil test Agro-Culture Liquid Fertilizers has two main foliar program options for soybeans. Depending on soil test levels, either a program of 3 gal/A Sure-K with 1 qt/A MicroLink Manganese or 2 gal/A fert-Rain are commonly used. For this experiment location, soil levels were medium to low on potassium with 70 ppm and 2.2% base saturation. In cases where potassium levels are medium, a foliar program including Sure-K would be a better option. In cases with higher potassium soils, ferti-Rain tends to work better. This experiment compared these two foliar programs applied at 3 different timings, keeping the total fertilizer rate for each product per acre for the season the same. Timings included (1) 1 application at V4, (2) 2 applications at V4 and R1 or (3) 4 applications at V4, R1, R2, and R3. (V4- 4  trifoliate, R1-beginning flower, R2-full flower, R3-beginning pod)

Soybean 11-508

Soybean 11-508 photo

Conclusions:

  • All foliar applications increased soybean yields over the untreated check by at least 3 bu/A.
  • With the soils in the experiment having medium potassium levels, there was no significant difference between the two foliar programs. However, at most timings, there was a slight advantage to the Sure-K with MicroLink Manganese application.
  • There was no statistically significant difference in soybean yield between the 3 timings of application. This shows, that a grower can apply a full rate in a single application or split the rate and “spoon feed” the crop if they are making multiple pesticide applications. It is a good practice to apply small amounts of nutrition when making any postemergence application.