K Fertilization Following Corn Stover Removal

Trial Type

P & K

General Stats

County
Edmunds
Replications
1
Crop
Soybean
Seed Brand
No Value
Variety
No Value
Relative Maturity
1.0
Tillage
Conventional Till
Irrigated
No Value
Drain Tile
No Value
Previous Crop
Corn
Row Sapcing
30"
Plant Population
150000
Plant Date
20/05/2014
Cover Crop
No Value
Seed Treatment
No Value

Soil Stats

Soil Type
Fine
Soil pH
4.0
Organic Matter
No Value

Methodology

250 lbs K2O/acre were broadcasted on May 30,2014 (417 lbs Potash 0-0-60) prior to planting soybeans across one 90-foot strip in Edmunds County.  This was accomplished in a part of the field that had corn stover removed the previous fall.  The average K soil test level for the strip was 382 ppm. The treated part of the field is under a center pivot irrigation system. The yield was collected with a combine mounted yield monitor.

Results

Looking at the whole strip, the check (untreated control) received a 42.275 bushel/acre yield while the K-fertilization strip yielded 42.17 bushels/acre, equating to a 0.19 bushel/acre loss to the K fertilization. However, site specific analysis resulted in a different conclusion.  Viewing the map above, the K strip advantages occurred on the shoulder and the depressional areas of the field.  In these areas, there where yield increases of 10-20 bushels occurred. This may be due to more K+ being available for the plant in the transpirational stream at these elevations. In other parts of the field, there was no difference or a yield reduction due to the K.  Our speculation is that this may be salinity related, but more work needs to be done.  Overall, at the rate applied, there was not a whole field positive yield response that economically justified K+ application.  In areas that resulted in a yield increase, optimum economic K rates need to be determined.

Rainfall

Temperature

Applications

  Event Date Type Application Method Amount
30/05/2014 K Surface broadcast 250 lbs / acre (actual)

Fertilizer Applications

  Event Date Type Application Method Amount
30/05/2014 K Surface broadcast 250 lbs / acre (actual)

Insecticide Applications

Fungicide Applications

Herbicide Applications