Alan Sundermeier, Extension Agriculture and Natural Resources Agent
Rich Bennett, Henry County Producer
Compare two different lime sources for their effect on soil test values and crop yields.
| Nearest Town: | Napoleon | Drainage: | Tile | |
| Soil type: | Millgrove loam | Crops: | 1995 - wheat 1996 - corn | |
| Tillage: | Conventional | 1997 - soybeans 1998 - corn |
In the same field, two different types of lime were applied to separate 45-foot-wide field-length strips in a randomized, complete block design. From Bucyrus, Ohio, a high calcium (Hi Ca) lime (analysis: 33% Ca, 4% Mg, 99% total neutralizing power or TNP ) was randomly applied to 6 strips. From Woodville, Ohio, a low calcium (Low Ca) lime (analysis: 23% Ca, 10% Mg, 107% TNP) was randomly applied to six strips.
Initial soil samples were taken in September 1995. In October 1995 two tons per acre of lime were applied according to plot design. In October 1996 corn yields were recorded for each strip and soil samples were taken. In November 1996 another two tons per acre of lime were applied according to plot design. In September 1997 soybean yields were recorded and soil samples were taken. In September 1998 corn yields were taken and soil samples were taken.
| Yields (bu/A) | 1996 Corn | 1997 Soybeans | 1998 Corn |
|---|---|---|---|
| Low Ca | 131.9 | 49.3 | 198.9 |
| Hi Ca | 128.9 | 50.6 | 201.2 |
| LSD (P = 0.05) | 6.3 | 1.6 | 5.3 |
| CV (%) | 3.3 | 1.8 | 1.5 |
| Significant Difference | No | No | No |
| pH | 9/95 | 10/96 | 9/97 | 9/98 |
|---|---|---|---|---|
| Low Ca | 5.57 | 5.43 | 6.07 | 6.12 |
| Hi Ca | 5.60 | 5.55 | 6.23 | 6.60 |
| LSD (P = 0.05) | 0.25 | 0.40 | 0.32 | 0.15 |
| CV (%) | 3.07 | 4.85 | 3.46 | 1.38 |
| Significant Difference | No | No | No | Yes |
| Ca % base saturation | 9/95 | 10/96 | 9/97 | 9/98 |
| Low Ca | 56.4 | 39.3 | 51.7 | 80.6 |
| Hi Ca | 57.7 | 46.8 | 61.7 | 62.0 |
| LSD (P = 0.05) | 4.08 | 14.5 | 12.0 | 5.01 |
| CV (%) | 4.82 | 22.7 | 14.2 | 4.0 |
| Significant Difference | No | No | No | Yes |
| Mg % base saturation | 9/95 | 10/96 | 9/97 | 9/98 |
| Low Ca | 16.5 | 11.0 | 16.0 | 24.6 |
| Hi Ca | 16.7 | 11.3 | 21.2 | 17.2 |
| LSD (P = 0.05) | 1.6 | 3.7 | 3.8 | 5.1 |
| CV (%) | 6.4 | 22.2 | 13.9 | 13.9 |
| Significant Difference | No | No | Yes | Yes |
The two different lime sources resulted in significantly different values for pH and Ca in the last year of this study and Mg in the last two years. However, an economic return for this lime was not realized since yields were not significantly different. The Hi Ca lime source cost was $4.50 per ton more than the low Ca lime source.
Initially in 1995, the test field had medium levels of soil calcium and high levels of magnesium; also the Ca/Mg ratio was over 3:1. Therefore, with a soil pH of 5.6 and a Ca/Mg ratio greater than 1:1, the farmer need only be concerned with raising the soil pH. The fineness of the lime and TNP (total neutralizing power) are the more important quality measures for comparing lime sources. As long as the soil Ca/Mg ratio is more that 1:1, the farmer need not worry about adding a concentrated Ca lime source. Raising soil pH is not necessarily related to the Ca and Mg content of the lime. Most northwest Ohio soils are not deficient in calcium.
A farmer should select the cheapest lime source that will neutralize the soil. The calcium and magnesium content of that lime is less important than TNP in most northwest Ohio soils. This study confirmed that yield was not affected by the type of lime applied.
For additional information, contact:
Alan Sundermeier
Ohio State University Extension, Henry County
104 E. Washington St., Suite 107
Napoleon, OH 43545
419-592-0806
sundermeier.5@osu.edu