Table 1.4-8A. Estimated grain yields for various planting dates and population rates
| Planting date | Plants/A at harvest | ||||||||
|---|---|---|---|---|---|---|---|---|---|
| 10,000 | 12,500 | 15,000 | 17,500 | 20,000 | 22,500 | 25,000 | 27,500 | 30,000 | |
| Optimum yield (percent) | |||||||||
| Source: Adapted from University of Illinois and Purdue University |
|||||||||
| April 10 | 62 | 70 | 76 | 82 | 86 | 90 | 92 | 94 | 94 |
| April 15 | 65 | 73 | 79 | 84 | 89 | 92 | 95 | 97 | 97 |
| April 20 | 67 | 74 | 81 | 86 | 91 | 94 | 97 | 98 | 99 |
| April 25 | 68 | 75 | 82 | 87 | 92 | 95 | 98 | 99 | 100 |
| April 30 | 68 | 75 | 82 | 87 | 92 | 95 | 98 | 99 | 100 |
| May 4 | 67 | 75 | 81 | 86 | 91 | 94 | 97 | 99 | 99 |
| May 9 | 65 | 73 | 79 | 85 | 89 | 93 | 95 | 97 | 97 |
| May 14 | 63 | 70 | 76 | 82 | 86 | 90 | 92 | 94 | 95 |
| May 19 | 59 | 66 | 73 | 78 | 83 | 86 | 89 | 90 | 91 |
| May 24 | 54 | 62 | 68 | 74 | 78 | 82 | 84 | 86 | 86 |
| May 29 | 49 | 56 | 63 | 68 | 73 | 76 | 79 | 80 | 81 |
| June 4 | 43 | 49 | 57 | 63 | 67 | 70 | 73 | 75 | 75 |
| June 9 | 36 | 42 | 49 | 56 | 60 | 62 | 65 | 67 | 68 |
