Like the other posters have said i believe even spacing is less important than even emergence.
Back in 2005 i measured the spacing on a field and calculated the expected yield loss. the following table shows the results. Keep in mind this calculated.
| | | | spacing | | | | | measured | between | | | | | location | each pair | | | | | of each | of plants | | | | | corn plant | measured | row spacing | | plant | | inches | inches | in inches | | 1 | | | 0 | 30 | | 2 | | 7 | 7 | | | 3 | | 11 | 4 | | | 4 | | 16.5 | 5.5 | | | 5 | | 21.5 | 5 | | | 6 | | 28.5 | 7 | | | 7 | | 34 | 5.5 | | | 8 | | 37 | 3 | | | 9 | | 50.5 | 13.5 | | | 10 | | 55 | 4.5 | | | 11 | | 66.5 | 11.5 | | | 12 | | 74 | 7.5 | | | 13 | | 83.5 | 9.5 | | | 14 | | 92.5 | 9 | | | 15 | | 98 | 5.5 | | | 16 | | 101.5 | 3.5 | | | 17 | | 110.5 | 9 | | | 18 | | 119 | 8.5 | | | 19 | | 121.5 | 2.5 | | | 20 | | 127 | 5.5 | | | 21 | | 136 | 9 | | | 22 | | 144.5 | 8.5 | | | 23 | | 151.5 | 7 | | | 24 | | 154.5 | 3 | | | 25 | | 158.5 | 4 | | | 26 | | 170.5 | 12 | | | 27 | | 175.5 | 5 | | | 28 | | 185 | 9.5 | | | 29 | | 193.5 | 8.5 | | | 30 | | 200 | 6.5 | | | 31 | | 207 | 7 | | | | | | | | | | | | | | | | | | | | | average | | | 6.9 | | | standard deviation | | 2.78 | | | yield loss | bu/acre | | 3.13 | | | plants/acre | | | 30302 | |
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corn plant spacing
