Steve Ruhl, Extension Agriculture and Natural Resources Agent
in cooperation with the Morrow County Soil and Water Conservation District
Objective: To examine the effect on corn yields when using K fertilizer on a soil with a low exchangeable K level.
Background |
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| Site:
Nearest Town: Major Soil Type: Tillage: Previous Crop: Soil test: |
Morrow County Home farm
Mt. Gilead Centerburg Conventional: CRP pH - 7.0 P - 44 ppm K - 90 ppm CEC - 9.3 |
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| Variety:
Planting Date: Fertilizer: |
Golden Harvest 2495
May 11 60 pounds N/ac as 28% with herbicides 130 pounds N/ac as 28% side dress on 6/9 K varied by treatment |
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| Harvest Date:
Herbisides: |
Pre: Post: | October 19
Balance - 2 oz. Atrazine - 1.8 pound Simazine - 0.9 pound Accent - 2/3 oz. Clarity - 8 oz. UAN - 3/4% v/v |
A replicated study using five replicates in a randomized complete block design was planned. The phosphorus reading of 44 ppm allowed us not to use phosphorus. The potash was applied in 40-foot wide plots at the rates of 0, 100, and 200 pounds per acre of 0-0-60. The individual harvested plots were 0.187 acres in size.
| Rate of Potash lbs/ac |
Corn Yield bu/ac |
| 0 | 163.7 a |
| 100 | 154.7 a |
| 200 | 167.1 a |
Treatment means followed by the same letter are not significantly different at P = 0.05
LSD = 17.2 bu/ac, cv = 2.3%
Ohio soils contain 10,000 to 20,000 ppm of total K. Only a few hundred ppm of K exist in the exchangeable (available) form readily available for plants. The K soil test level for the site of the trial would be regarded as less than optimum for corn production.
The yields in this trial were good despite a fairly dry crop year. The yields were not significantly different. This trial will be repeated another three years - two years in soybeans and one additional year in corn.
For additional information, contact:
Ohio State University Extension, Morrow County
871 W. Marion Rd., Suite 102
Mt. Gilead, OH 43338
419-947-1070
ruhl.1@osu.edu