- In general, the influence of row spacing on maize yield and quality was minimal and inconsistent. By contrast, the effects of population on yield and quality were significant and generally predictable.
- Reducing row spacing did not significantly affect yield or quality at normal plant populations (~90,000 plants/ha) up to a plateau, usually at 120,000 plants/ha. Profitability increased by $100-$1000/ha.
- Thousand kernal weight consistently declined with increased population (by about 1g for every additional 10,000 plants/ha).
- The response of bulk density to population varied unpredictably from nil to negative.
- In this research all plants were accurately spaced so any impact of planter on accuracy of seed placement has not been evaluated.