Effect of Row Direction on Corn Grain Yield in Silage Production


  • Where terrain permits, corn rows can be planted in either a north-south or an east-west direction.
  • Sunlight penetrates more deeply into the plant canopy with north-south than with east-west rows.


  • Compare corn grain yields in silage production between corn rows planted north-south versus east-west directions. 
  • Compare grain yields at 2 plant populations.

Study Description

Location:                     1 in central Illinois

Years:                            2011-2012

Hybrids:                        2 in 2011, 3 in 2012

Row Spacing:              30 inches


    Row Direction:        North-south, East-west

      Plant Population   28,000 and 34,000 plants/acre

  • Grain yield, kernel weight and kernels/ear were measured at the time of silage harvest.


Row Direction

  • Corn grain yield was significantly greater in north-south rows than in east-west rows in 2011, but did not differ between row directions in 2012.
  • The average yield advantage of north-south rows over the 2 years of the study was 10%.
  • The greater yield observed in north-south rows was largely attributable to significantly greater kernel weight.
  • Number of kernels/ear was significantly greater in north-south rows in 2011 but not 2012.
Chart: research results

Plant Population

  • Grain yield was significantly greater with a plant population of 34,000 plants/acre than 28,000 plants/acre in both years of the study.
  • The average yield advantage with the greater plant population was 25% over the 2 years of the study.
  • The greater yield was primarily due to more ears/acre.
  • Kernel weight was not affected by plant population.
  • Plant population effect on kernels/ear was inconsistent between the 2 years of the study.

Research conducted by Dr. Paul Walker, Illinois State University, as a part of the Pioneer Crop Management Research Awards (CMRA) Program. This program provides funds for agronomic and precision farming studies by university and USDA cooperators throughout North America. The awards extend for up to 4 years and address crop management information needs of Pioneer agronomists, sales professionals and customers.

2011-2012 data are based on average of all comparisons made in one location through Dec. 31, 2012. Multi-year and multi-location is a better predictor of future performance. Do not use these or any other data from a limited number of trials as a significant factor in product selection. Product responses are variable and subject to a variety of environmental, disease, and pest pressures. Individual results may vary.