Dr. Steve Prochaska, Extension Agriculture and Natural Resources Agent
To compare wheat yields grown at 7.5 and 15-inch row widths.
| Test Site: | Ohio State University | Soil test: | pH 5.8, P 21 ppm, |
| Unger Farm | K 163 ppm | ||
| County: | Crawford | Fertilizer: | 127-69-60 actual NPK |
| Soil type: | Pewamo clay loam and | applied per acre | |
| Blount silt loam | Planting date: | October 2, 2001 | |
| Tillage: | Disk | Planting rate: | 120 lb/A |
| Previous crop: | Soybeans | Row width: | 7.5 and 15 inch |
| Variety: | See table | Herbicide: | 2,4-D 1 pt/A |
| Harvest date: | July 8, 2002 |
A completely randomized design with six replications in small plots (5.5 x 50 feet) in each of three years was used to evaluate the effect of row width on wheat yield. Treatments were 7.5 and 15-inch row wheat. Wheat was planted with a three-point hitch-mounted tool-bar planter equipped with sunflower openers. Wheat harvest was done with a small plot combine.
| 7.5-inch rows | 15-inch rows | F-test | LSD (0.05) | |
| Year and Variety | (bu/A) | (bu/A) | (bu/A) | |
| 2000 I9824 | 72.3 | 70.8 | <1 | NS |
| 2001 Agra 962 | 86.7 | 79.2 | 14.5 | 4.4 |
| 2002 Agra 962 | 85.1 | 76.8 | 28.3 | 3.5 |
| Average | 81.5 | 75.6 | ||
What level of wheat yield can be expected from wheat grown in 15-inch rows vs. the row spacing of 7.5 inches? With the new technology of polymer-coated soybeans, this question is important to producers evaluating the profitability of such systems as modified relay intercropping. In the first year of this study, the yield of wheat grown in two different row widths was not significantly different. In the second and third years, yield was significantly different with higher yields with the narrower row wheat planting. When comparing the two treatments over the three-year period, yields were not significantly different.
The yield difference over the three years varied from 2 to 7.5 bu/A. This result was consistent with work done by Beuerlein et al. (Profitable Wheat Management, Extension Bulletin 811, page 18) on the effect of row spacing on wheat yield in Ohio.
For further information, contact:
Dr. Steve Prochaska
Ohio State University Extension
117 E. Mansfield St.
Bucyrus, Ohio 44820
prochaska.1@osu.edu