Phil E. Rzewnicki, Extension Associate, On-Farm Research Coordinator
Charles Eselgroth, Ross County Farmer
Peter Thomison, Extension State Specialist, Corn Production
Grain crops grown organically often are raised in conditions unlike that experienced in university and commercial variety performance trials. The objective of this trial was to determine if varieties suited to high input conditions are the same as those suited to low input conditions.
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Table 1. Certified Organic Farms Participating in Statewide
Performance Trials, Row Widths, Planting Dates, and Harvest
Dates for the Corn Test Plots.
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| Farm No. |
Region of State |
County | Nearest Town |
Farm | Row Width (in) |
Planting Date |
Harvest Date |
| 1 | Northwest | Defiance | Mark Center | Joe Hammond | 30 | 5/9/00 | 11/4/00 |
| 2 | North-Central | Sandusky | Clyde | Jeff Dean | 22 | 5/20/00 | 11/13/00 |
| 3 | North-Central | Medina | Litchfield | Gary Mennell | 30 | 6/3/00 | 12/4/00 |
| 4 | Northeast | Wayne | Wooster | Art Riggenbach | 30 | 5/16/00 | 11/30/00 |
| 5 | Central | Delaware | Delaware | Stratford Center | 30 | 5/12/00 | 12/10/00 |
| 6 | Central | Knox | Centerburg | Stuart Veatch | 30 | 5/14/00 | 11/15/00 |
| 7 | Central | Knox | Mt. Vernon | Rex Spray | 30 | 5/16/00 | 11/2/00 |
| 8 | West | Darke | Union City | Dan Young | 30 | 5/14/00 | 11/20/00 |
| 9 | West-Central | Logan | DeGraff | David Bell | 30 | 5/17/00 | 11/22/00 |
| 10 | South | Ross | Greenfield | Charlie Eselgroth | 30 | 5/16/00 | 11/21/00 |
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Table 2. Soil Types and Soil Test Levels for Test Plots on Participating Farms.
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| Farm No. |
Soil Type | Ph | P (ppm) |
K (ppm) |
Ca (ppm) |
Mg (ppm) |
O.M. (%) |
Nitrate (ppm) |
| 1 | Nappanee silt loam | 7.6 | 11 | 117 | 3750 | 753 | 3.3 | 7.1 |
| 2 | Hoytville clay loam | 6.4 | 18 | 108 | 1820 | 299 | 3.7 | 9.9 |
| 3 | Mahoning silt loam | NA | NA | NA | NA | NA | NA | NA |
| 4 | Hoytville silt loam | 7.2 | 56 | 120 | 1880 | 221 | 3.5 | 13.0 |
| 5 | Blount silt loam | 6.2 | 8 | 79 | 1670 | 282 | 3.1 | 17.1 |
| 6 | Bennington silt loam | 5.6 | 12 | 70 | 1130 | 251 | 2.7 | 12.3 |
| 7 | Chili & Bogart silt loams | 5.6 | 31 | 112 | 950 | 163 | 2.9 | 12.8 |
| 8 | Miamian & Crosby silt loams |
6.2 | 36 | 156 | 1760 | 433 | 3.1 | 26.3 |
| 9 | Miamian silt loam | 6.8 | 38 | 107 | 1600 | 415 | 3.1 | 13.3 |
| 10 | Miamian silt loam | 6.5 | 21 | 86 | 1690 | 305 | 3.1 | 14.4 |
| NA= not available. | ||||||||
The corn varieties evaluated for the project included the following:
Agrigold A6447 yellow food grade with pink cob and 109-day maturity
Baldridge 611 a corn silage variety with yellow and white kernels and 112-day maturity
Bird ND-70 a nutrient dense corn, yellow grain, red cob with a 111-day maturity
Cash RS (OP) an open-pollinated variety, yellow grain, red cob with a 113-day maturity
Doebler 636XY yellow grain with pink cob and 109-day maturity
French's 440 yellow grain with red cob and 108-day maturity
NC+Organics 4880 yellow grain with white cob and 110-day maturity
Pioneer 34K77 yellow food grade with white cob and 107-day maturity
Schlessman 550 3-way cross, yellow grain with variable cob color and 108-day maturity
Steyer Seed 2340 yellow grain with red cob and 106-day maturity
White Cap (OP) an open-pollinated variety, yellow grain, white or pink cob, 85-day maturity
Yoders 510 yellow corn, white cob with 108-day maturity.
The study was conducted as a randomized complete block design using the 10 farms as blocks or replicates. Twelve varieties were selected by producers at a planning session to prepare for the study. These varieties included food-grade and feed-grade corn. Two open-pollinated varieties were added to the selections to respond to inquiries regarding their performance in Ohio. The varieties were randomized at each farm (one replication per location) in field length strips averaging nearly 1,200 feet in length with widths varying from 10 to 60 feet (4 rows to 24 rows), but averaging 24 feet. Farmers were instructed to use planting rates they normally use with the only seeding rate recommendations being for Baldridge 611 and Cash RS. Providers of the seed for those two varieties recommended rates should be kept close to 20,000 seeds per acre.
Producers were asked to record the date for each variety when half the plants had achieved the R1 growth stage (first leaf unfolded after emerging). Soil samples were taken approximately three to four weeks after planting, corresponding to what would be the time of sampling for sidedress nitrogen recommendations in conventional fields. Early season stand and height data were the averages of five replicates per variety per farm taken at soil sampling time.
The entire plot area was harvested at Farm No. 2, 3, 6, 7, 8, and 9 to reduce operator inconvenience. Farm No. 1 harvested the west three rows of six-row strips; Farm No. 10 harvested the center four rows of six-row strips. Farms No. 4 and 5 harvested ears of corn by hand using 40-row-feet and 80-row-feet samples respectively. All other data, other than yield, grain moisture, and test weight, were taken from the center two rows of each variety strip plot.
All but one of the fields sampled showed low levels of nitrate-nitrogen in the soil. These fields, had they been conventional fields, would have had nitrogen fertilizer applied to achieve optimum corn yields (e.g., Iowa recommendations would suggest additional N for nitrate levels below 21 ppm.). Farms No. 5 and 6 were below optimum P and K levels. Farm No. 1 was below optimum P and Farm No. 10 was below optimum K.
| Table 3. Early Season Growth and Development. | ||||
| Variety | Emergence1 (%) |
Days to Emergence2 |
Height 3-4 Weeks After Planting (in) |
Growth Rate - Emergence to 25th Day2 (in/day) |
| Agrigold A6447 | 92.5 ab | 9.1 a | 6.8 cde | 0.36 cd |
| French's 440 | 91.6 abc | 9.9 bc | 8.0 a | 0.44 a |
| Doebler 636XY | 92.2 ab | 9.5 ab | 7.4 abc | 0.41 abc |
| NC+ Organics 4880 | 94.5 ab | 10.1 bcd | 6.5 de | 0.37 bcd |
| Pioneer 34K77 | 91.7 abc | 9.5 ab | 6.9 bcd | 0.37 bcd |
| Steyer 2340 | 84.4 cd | 9.8 abc | 7.6 ab | 0.42 ab |
| Bird ND-70 | 89.3 bcd | 9.8 abc | 7.2 bcd | 0.41 abc |
| Yoders 510 | 76.2 e | 11.3 e | 5.4 f | 0.34 d |
| Baldridge 611 | 97.7 a | 10.8 de | 6.6 de | 0.41 abc |
| Schlessman 550 | 84.3 cd | 9.8 abc | 6.2 e | 0.37 bcd |
| White Cap (OP) | 83.6 de | 9.6 ab | 6.9 bcd | 0.37 bcd |
| Cash RS (OP) | 91.2 abcd | 10.4 cd | 7.2 bcd | 0.42 abc |
| Average all varieties | 89.2 | 9.9 | 6.9 | 0.39 |
| LSD (0.05) | 7.6 | 0.7 | 0.75 | 0.055 |
| CV % | 9.6 | 7.5 | 11.9 | 14.5 |
| 1 Planting rates across farms averaged 23,726
seeds per acre except White Cap at 22,692 seeds per acre and
Baldridge and Cash RS both at 21,742 seeds per acre.
2 Emergence date for each variety not collected at two farms. Means followed by the same letter are not significantly different from each other. |
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| Table 4. Agronomic Performance of Corn at Harvest. | |||||
| Variety | Yield1 (bu/A) |
Harvest Population2 (plants/A) |
% of Seeding Rate2 |
Harvest Moisture (%) |
Test Weight (lbs/bu) |
| Agrigold A6447 | 124.6 a | 22,511 a | 93.6 a | 21.9 d | 54.72 c |
| French's 440 | 118.8 ab | 21,372 a | 88.7 ab | 19.6 ab | 53.99 cde |
| Doebler 636XY | 114.9 ab | 21,657 a | 89.8 a | 20.0 b | 52.64 fg |
| NC+Organics 4880 | 114.6 ab | 21,056 ab | 87.5 abc | 20.7 bcd | 53.40 ef |
| Pioneer 34K77 | 112.3 ab | 21,407 a | 88.8 ab | 19.9 b | 56.03 a |
| Steyer 2340 | 107.6 bc | 21,093 ab | 87.7 abc | 20.2 bc | 53.59 def |
| Bird ND-70 | 95.8 cd | 21,852 a | 91.1 a | 19.2 ab | 55.95 ab |
| Yoders 510 | 86.0 d | 18,817 cd | 78.3 d | 21.5 cd | 53.25 ef |
| Baldridge 611 | 61.2 e | 19,718 bc | 90.3 a | 21.8 d | 54.69 cd |
| Schlessman 550 | 59.9 e | 19,533 bcd | 81.0 d | 19.8 b | 54.84 bc |
| White Cap (OP) | 49.4 ef | 18,746 cd | 81.8 cd | 18.3 a | 54.76 c |
| Cash RS (OP) | 39.9 f | 18,088 d | 83.0 bcd | 23.4 e | 51.76 g |
| LSD(0.05) | 15.2 | 1,570 | 6.4 | 1.5 | 1.13 |
| CV% | 18.3 | 8.2 | 7.8 | 8.3 | 2.3 |
| 1 Yields adjusted to 15.0% grain moisture.
2 Data missing from one farm. Means followed by the same letter are not significantly different. |
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Excessive rain in the northern areas of the state, particularly in the central and eastern sections, delayed planting for participating producers. Originally, plans were to have 14 certified organic farms participate in the trial; however, only 11 farms were able to plant corn successfully. The excessive moisture also hindered weed control after planting. The very wet conditions in June resulted in one less rotary hoe or cultivation pass than the producers normally plan. Not all the varieties in one planted field flowered normally, and the field was chopped for silage.
Organic grain producers regard early plant vigor as an important characteristic of varieties for their weed management programs. Normally, planting is done later than conventional farms to mechanically control early occurring weeds. Once the corn emerges, fast growth is desirable to compensate for late planting and to provide a canopy over weeds that emerge after planting. Of the varieties tested in this trial, the Agrigold hybrid was the quickest to emerge at 9.1 days after planting. This was not significantly different from the Bird, Doebler, Pioneer, Schlessman, Steyer, and White Cap varieties. Of this early emerging group, Bird, Doebler, and Steyer had the greatest growth rate. French's was significantly taller at three to four weeks after planting than any other variety with the exception of Doebler and Steyer.
Organic producers have a difficult time attaining seed that is not commercially treated. For this trial, all of the varieties were treated, except for the two open-pollinated and Yoders. (Permission was attained from the International Office of the Organic Crop Improvement Association so that the certification status of participating producers would not be jeopardized by the use of chemically treated seed.) Interestingly, Yoders had an emergence of only about 80% of the seeding rate (Table 4), which was significantly lower than all other varieties with the exception of White Cap (OP). The Yoders and Baldridge varieties were significantly slower than all other varieties in number of days to emergence after planting. The other untreated variety, Cash RS, was in the mid-range of performance in regards to emergence.
Agrigold A6447 yielded significantly better than all the other varieties with the exception of French's 440, Doebler 636XY, NC+Organics 4880, and Pioneer 34K77. One drawback to the Agrigold A6447, however, was its tendency to be among the varieties that remain high in harvest moisture. The Agrigold variety's harvest moisture was significantly greater than three of the varieties that were equivalent in yield. Grain-drying costs are a significant management factor for certified organic producers. The open pollinated varieties used in this trial performed poorly, largely due to excessive lodging, stalk breakage, and barren plants relative to the other varieties. At several farm sites, the two open-pollinated lines were already lodging severely by silk time. The open pollinated varieties consistently yielded less than half of the yields obtained by the better performing hybrids.
In general, the varieties were grown under typical organic farm conditions with moderate weed pressure and marginally low soil fertility. The results are only for one season. This trial will be repeated next year to further confirm the performance of promising varieties.
The authors would like to express their appreciation to all the participating producers for their time and efforts. Thanks are also due to the North Central Region Sustainable Agriculture Research and Education Program for providing a producer grant. We also appreciate the assistance of OSU Agricultural Technical Institute student Rhonda Rinehart for data collection during the summer. We would also like to thank the seed companies involved for providing free or discounted seed for the project. Producer Gary Mennell and Rich Pratt, OARDC plant breeder, also provided free seed of the open-pollinated lines.
For more information, contact:
Phil Rzewnicki, On-Farm Research Coordinator
Horticulture and Crop Science
The Ohio State University
202 Kottman Hall
2021 Coffey Road
Columbus, OH 43210
614-292-0117
rzewnicki.1@osu.edu