We used the 30 year normal temperatures and the weekly precipitation amounts to simulate these averages. Each soil monolith has a drainage system to allow water to drain through the soil profile. Soil moisture sensors measured the upper 10 cm of the soil profile. In the first experiment, the maize hybrid Northrup King N68B 3111 was planted in with two rows of five plants in each row to simulate a population density of 100,000 plants ha−1 similar to a typical plant population for maize production in the Midwest. All monolith blocks were treated with the equivalent of 180 kg ha−1 of nitrogen with all other nutrients provided to be adequate for maize production.