Gary Wilson, Extension Agent, Agriculture and Natural Resources
Ed Lentz, Extension District Specialist, Agronomy
To evaluate the effects of deep ripping on corn yields.
| Cooperator: | Jim Kuhlman | Fertilizer: | Broadcast and |
| County: | Hancock | incorporated May 12 | |
| Nearest Town: | Findlay | 300 lb/A 46-0-0 | |
| Drainage: | Naturally poorly-drained | 300 lb/A 9-23-30 | |
| Soil type: | Millgrove/Colwood | Planting Date: | May 14, 2002 |
| silt loam | Planting Rate: | 29,000 seeds/A | |
| Tillage: | Conventional till | Row Width: | 30-inch |
| Previous Crop: | Soybeans | Herbicides: | 24 oz/A Liberty |
| Hybrid: | NK 45A6 | Harvest Date: | October 31, 2002 |
| Soil test: | none |
Experimental design was a randomized complete block with three treatments replicated four times. Treatments were fall deep ripping at 8 and 14 inches by an Unverferth In-line Ripper and a zero check followed by conventional practices in the spring. Plots were 40 feet wide and 1,530 feet long. Plot yields were measured with a weigh wagon. Yield was adjusted to 15% moisture. Harvest population was estimated by counting plants from 17.4-foot sections of two center rows per plot.
Table 1. Treatment Means for Yield, Moisture, and Population.a
| Deep Ripping | Grain | Harvest | Harvest |
| Depth | Yield | Moisture | Population |
| (inches) | (bu/A) | (%) | (plants/A) |
| 14 | 63.1 a | 17.3 a | 18,750 a |
| 8 | 61.9 ab | 17.4 a | 19,750 a |
| 0 | 55.9 b | 17.6 a | 21,125 a |
| LSD (0.05) | 6.7 | NS | NS |
| F-test | 18.8 | <1 | <1 |
| a Means followed by the same letter within a column are not significantly different. | |||
Deep ripping had larger yields than the zero check at the 14-inch depth. The 8-inch depth was similar to the zero check. However, yields overall were greatly reduced by abnormally hot and dry conditions during the growing season. Normally yields would be between 175 and 200 bu/A. No differences were detected for harvest moisture and population. Populations were lower than most years, which also may have contributed to lower yields. Conditions were cold and wet during planting which may have caused the stand reduction.
Deep ripping at 14 inches in the fall may be a benefit in stress years. This benefit may have been the result of improved soil conditions for root development. However, yields were so low that conclusive statements should not be made until further research has been completed from a more normal growing season.
For more information, contact:
Gary Wilson
Ohio State University Extension,
Hancock County
7868 CR 140, Suite B
Findlay, OH 45840
491-422-3851
wilson.26@osu.edu
Ed Lentz
Ohio State University Extension,
Northwest District
1219 W. Main Cross St., Suite 202
Findlay, OH 45840
419-422-6106
lentz.38@osu.edu