Table 1.4-8A. Estimated grain yields for various planting dates and population rates.

Table 1.4-8A. Estimated grain yields for various planting dates and population rates. Figures shown are most applicable to corn fields with greater than 125 bushels per acre.
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: University of Illinois
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

Agronomy Guide 2009–2010