Corn Production Studies

Corn Farm Research Production Studies

Farm research studies in this section include row spacing, tillage system, residue, cover crop, plant population/planting speeds, and other production studies.  All studies are pdf documents and require Adobe Acrobat Reader. Download free.

Row Spacing Studies

Objective:  Determine the profitability of narrow row (15") versus wide row (30") irrigated corn production.
Summary:  (Nielsen) Grain yield was slightly higher from the 15-inch rows in 2004; possibility due to wide guess rows next to the 15-inch rows. In 2005, grain yield was significantly lower for the 15-inch rows. 
(Grimes) Grain yield was lower and grain moisture at harvest higher where 15-inch rows were used in 2004. Plant population was significantly lower in the 15-inch rows which may account for the lower yield.
(Chvatal) Row width had no effect on yield, however, grain moisture at harvest was higher with 15" rows in 2003. In 2004 grain yield was lower in 15" rows. There appeared to be more lodging and harvest loss ini the narrows rows.
(Ohnoutka) Grain yield was not significantly affected by row spacing even though there was a difference in plant population. Grain moisture was lower and test weight was higher at the lower population in the wider rows.
(Stork) No significant differences were measured in 1995. In 1996 yield difference was no significant. Population and test weight were slightly higher and moisture lower with wide rows.

Tillage System Studies

Objective:  Determine the profitability of a no-till corn and soybean rotation versus a tilled system.

Summary:  (Kremlacek) Growth and seed yield of soybeans was not affected by tillage in 2001. In 2002, tillage resulted in lower grain moisture at harvest and slightly higher test weight for corn. In 2003, tillage resulted in slightly lower soybean seed test weight. Plant stands for corn were higher with tillage in 2004 and grain yield was significantly higher. In 2005, seed yield of soybeans was significantly higher with tillage. Corn yield was signifantly higher with tillage in 2006. Tillage had no effect on soybeans in 2007. Excellent erosion control has been observed in the no-till treatments. (Stewart) The no-till treatment yield was higher than the conventional tillage treatment yield in 1993.

Objective:  Determine the profitability of in-furrow deep ripping versus none in dryland corn.
Summary:  There was no statistical yield difference in 1994 and no conclusions can be drawn from 1995 since it was not a randomized comparison.

Objective:  Determine the profitability of pre-plant row preparation vs. none in corn.

Objective:  Determine and document the effect of strip tillage on the profitability of irrigated corn after corn crop production.
Summary:  Strip-tillage increased the grain yield of irrigated corn (corn after corn) but did not increase yield in corn after dryland soybeans or corn after dryland corn. 

Objective:  Evaluate the effect of shredding stalks prior to planting vs. not shredding and its effect on yield and profitability.
Summary:  All four fields tested by Quad County producers in 2004 and 2005 showed no significant yield advantage to shredding vs. not shredding stalks.

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Residue Studies

Objective:  Determine the profitability of leaving versus parting existing soybean residue prior to corn planting. NOTE: Soybean residue was removed two weeks prior to corn planting when early preplant herbicide was applied.
Summary:  (Buller)  Pre-cleaning of rows prior to planting into soybean residue had no effect on the growth and yield of corn in 2004, 2005 or 2006. Pre-cleaning of rows of corn residue prior to planting in 2005 resulted in increased corn yield. 
(Mulliken) Removal of soybean residue prior to corn planting resulted in a significant yield increase in 1998. In 1999 residue removal had no significant effect on growth and grain yield of corn. Grain yield was significantly higher in 2000 where soybean residue was removed prior to planting. Grain moisture was slightly lower where residue was removed. In 2001 removal of soybean residue resulted in increased yield and slightly lower plant population. Removal of residue in 2002 resulted in slightly lower grain test weight.

Objective:  Evaluate the effect of shredding stalks prior to planting vs. not shredding and its effect on yield and profitability.
Summary:  All four fields tested by Quad County producers in 2004 and 2005 showed no significant yield advantage to shredding vs. not shredding stalks.

Objective:  Determine the profitability of removing soybean residue two weeks prior to corn planting (when early preplant herbicide is applied) versus during corn planting.
Summary:  Pre-cleaning of rows prior to planting into soybean residue had no effect on the growth and yield of corn in 2004, 2005 or 2006. Pre-cleaning of rows of corn residue prior to planting in 2005 resulted in increased corn yield.

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Cover Crop Studies

Objective:  Determine the profitability of growing a cover crop in a corn and soybean rotation.
Summary:  The use of a cover crop resulted in a reduced grain yield in 2008. This could be due to nitrogen being found in the biomass of the cover crop.  In 2004 grain yield was lower where a cover crop was planted the previous fall.

Planting - Population, Depth, and Speed Studies

Objective: Determine the profitability of different planting populations in the production of non-irrigated corn.
Summary: (Hanke) In 2001 the medium plant population (18,000 plants/ac) resulted in maximum grain yield which was significantly higher than the low plant population. Additional plants did not affect grain yield. In 2002 and 2003 grain yields were not influenced by planting population.
(Bartek) In 2001 plant population had no effect on grain yield or grain moisture at harvest. In 2003 higher planting rate did not effect yield, however, grain moisture was lower at harvest. In 2004 grain yield was increased by higher planting rate.
(Rolofson) In 1995 both test weight and moisture were significantly different. The low planting population yield narrowly missed being significant. In 1996 no residual effects were found. Yields measured by the yield monitor were slightly higher than where the weigh wagon was used. Grain yield was increased in 1997 by using the higher planting rate.
(McNamara) In 2010 the higher plant population resulted in significantly higher grain yield and profit per acre.
(Williams) In 2009, increasing the planting rate did not increase grain yield; however, the higher plant population resulted in wetter grain at harvest. In 2010, increased planting rate gave a higher grain yield with no change in grain moisture.

Objective: Determine & document the effect of seed planting depth in corn production.
Summary: (ARDC) 2010 Planting depth had no effect on corn yield or grain moisture at harvest in 2010.
(Bowman) 2010 Grain yield was increased significantly by planting deeper in both studies in 2009. Planting depth had no effect on grain yield in 2010.
(Mulliken) 2010 Planting deeper resulted in a significant reduction in grain yield in 2010.

Objective:  Determine the profitability of various planting speeds on corn yield.
Summary:  (Sabata)  Planting speed had no significant effect on grain yield in 2000. The two hybrids grown were significantly different in terms of grain yield.  In 2001 the difference in grain yield due to planter speed was significant which suggested that the optimum planting speed was 5 mph. Small seed size resulted in slightly higher grain yield. Need plant density values to determine if that is a factor. Grain yield was not affected by planting speed in 2002, however, planting at 4.5 mph resulted in drier grain at harvest and planting at 6.0 mph resulted in the highest plant population. In 2003 planting speed nor seed class had any effect on grain yield or moisture.
(Ellermeier) In 1999 grain yield was significantly lower where corn was planted at 6 miles per hour. Since plant population was not determined, it is unknown whether yield loss is due to lower population, poor seed spacing or another factor. Grain test weight was slightly higher where corn was planted at 3 miles per hour. In 2000 grain yield was again lower when corn was planted at 6 miles per hour.

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Other Production Studies

Objective:  Determine and document the effect of using genetically modified hybrids on the profitability of producing corn following soybeans.
Summary:  In 2003, the use of a Bt Hybrid resulted in lower yield and drier grain at harvest. Yield, grain moisture at harvest and test weight were not affected by YieldGard in 2004. In 2005, Roundup Ready Hybrid yielded significantly less than the non-Roundup Ready Isoline.

Objective:  Determine the profitability of using Bt versus non-Bt corn hybrids.
Summary: In 1998 insect population was too low to warrant insecticide application. There was no significant difference in yield between the two hybrids. The grain of the Bt corn was wetter at harvest and had a lower test weight. Insect population was again too low in 1999 to warrant insecticide application. The grain of the Bt Corn was again wetter at harvest. In 2000, insect population was again too low to warrant insecticide application. The grain of the Bt corn was again wetter at harvest and had a slightly higher test weight. Grain yields for the two hybrids were the same all three years.

Objective:  Determine the accuracy of using a combine yield monitor versus weigh wagon versus certified scale to verify crop yield.
Summary:  Calculated yields (bu/ac) were not significantly different between scale weights and monitor weights, however, grain moisture values averaged 0.6% lower with the yield monitor. For total yields, measurements with the monitor were slightly higher. The absolute error was 2.6% for corn and 2.2% for soybeans. The observed error was 1.4% for corn and -0.6% for soybeans.

Objective:  Determine the profitability of a corn/soybean rotation vs. continuous corn production.
Summary:  The corn following soybeans yielded significantly higher than the continuous corn.

Objective:  Determine the profitability of early versus conventional harvest date in commercial corn production.
Summary:  In 1998 corn harvested early contained 13.5% more moisture than the late harvested corn. When corrected for moisture, the early harvest resulted in significantly higher yield. Field loss was slightly higher for the late harvest. Upon adjusting for field losses, the yield for early harvest corn was still significantly higher. In 2001 early harvested corn contained 13.3% more moisture. When corrected for moisture the early harvested corn yielded only slightly more and there was no difference in field losses. These results do not agree with the 1998 results, however, two different hybrids were grown.

Objective:  Determine the profitability of relay cropping wheat into seed corn residue followed by soybeans versus a conventional corn and soybean rotation.

Summary:  Relay cropping was less profitable than conventional cropping in 2004 due to reduced yields of soybeans planted in wheat and exceptional conventional soybean yield. In 2005, relay cropping was more profitable than conventional cropping.

Objective: To determine & document the effect of applying growth promoters at planting on the profitability of corn production.
Summary: Yields in 2010 were not significant due to treatment. Yield for Jumpstart was slightly higher than the Check. Grain moisture at harvest was lower than the treated plots.

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