MP437

Corn ProductionHANDBOOK

University of Arkansas, United States Department of Agriculture, and County Governments Cooperating

The editors would like to thank Dr. William Johnson, former Extension Agronomist - Wheat and Feed Grains, for his significant contributions to this handbook.

Issued in furtherance of Cooperative Extension work, Acts of May 8 and June 30, 1914, in cooperation with the U.S. Department of Agriculture, Director, Cooperative Extension Service, University of Arkansas. The Arkansas Cooperative Extension Service offers its programs to all eligible persons, regardless of race, color, national origin, religion, gender, age, disability, marital or veteran status, or any other legally protected status, and is an Affirmative Action/Equal Opportunity Employer.

ContentsIntroduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1

1 – Growth and Development . . . . . . . . . . . . . . .3

2 – Cultural Practices . . . . . . . . . . . . . . . . . . . . .7Land Selection . . . . . . . . . . . . . . . . . . . . . . .7Seedbed Preparation . . . . . . . . . . . . . . . . . .7Planting Precision . . . . . . . . . . . . . . . . . . . .7Planting Date . . . . . . . . . . . . . . . . . . . . . . . .8Seeding Rate and Plant Populations . . . . . .9Hybrid Selection . . . . . . . . . . . . . . . . . . . . .10Growing Degree Days . . . . . . . . . . . . . . . .11

3 – Drainage and Irrigation . . . . . . . . . . . . . . . .13Drainage . . . . . . . . . . . . . . . . . . . . . . . . . . .13• Surface Drainage . . . . . . . . . . . . . . . . . .13• Internal Drainage . . . . . . . . . . . . . . . . . .14Irrigation . . . . . . . . . . . . . . . . . . . . . . . . . . .15• Yield . . . . . . . . . . . . . . . . . . . . . . . . . . . .15• Water Needs . . . . . . . . . . . . . . . . . . . . . .15• Irrigation Scheduling . . . . . . . . . . . . . . . .16• Irrigation Termination . . . . . . . . . . . . . . .17Irrigation Methods . . . . . . . . . . . . . . . . . . .18• Flood (Levee) Irrigation . . . . . . . . . . . . . .18• Furrow Irrigation . . . . . . . . . . . . . . . . . . .19• Border Irrigation . . . . . . . . . . . . . . . . . . .20• Center Pivot Irrigation . . . . . . . . . . . . . . .21Arkansas Situation . . . . . . . . . . . . . . . . . . .22

4 – Fertilization and Liming . . . . . . . . . . . . . . .23Soil pH . . . . . . . . . . . . . . . . . . . . . . . . . . . .23Nitrogen . . . . . . . . . . . . . . . . . . . . . . . . . . .23Animal Manures . . . . . . . . . . . . . . . . . . . . .25Phosphate and Potash . . . . . . . . . . . . . . . .25Calcium, Magnesium and Sulfur . . . . . . . .26Micronutrients . . . . . . . . . . . . . . . . . . . . . . .26Plant Analysis . . . . . . . . . . . . . . . . . . . . . . .27

5 – Major Insect Pests of Field Corn in Arkansasand Their Management . . . . . . . . . . . . . . . .29

Chinch Bug . . . . . . . . . . . . . . . . . . . . . . . . .29Corn Flea Beetle . . . . . . . . . . . . . . . . . . . .30Corn Thrips . . . . . . . . . . . . . . . . . . . . . . . . .31Cutworms Including the Black Cutworm . .32Seedcorn Maggot . . . . . . . . . . . . . . . . . . . .32Sugarcane Beetle . . . . . . . . . . . . . . . . . . . .33White Grub . . . . . . . . . . . . . . . . . . . . . . . . .33Wireworm . . . . . . . . . . . . . . . . . . . . . . . . . .34Aphids Including the Corn Leaf

and Bird Cherry-Oat aphids . . . . . . . . .35Corn Earworm . . . . . . . . . . . . . . . . . . . . . .35European Corn Borer . . . . . . . . . . . . . . . . .36Southwestern Corn Borer . . . . . . . . . . . . . .37Fall Armyworm . . . . . . . . . . . . . . . . . . . . . .40References . . . . . . . . . . . . . . . . . . . . . . . . .40Acknowledgments . . . . . . . . . . . . . . . . . . .41Photo Descriptions . . . . . . . . . . . . . . . . . . .42

6 – Diseases and Nematodes . . . . . . . . . . . . . .45Seed Rots and Seedling Blights . . . . . . . .45Crazy Top . . . . . . . . . . . . . . . . . . . . . . . . . .45Anthracnose . . . . . . . . . . . . . . . . . . . . . . . .46Gray Leaf Spot . . . . . . . . . . . . . . . . . . . . . .46Southern Corn Leaf Blight . . . . . . . . . . . . .46Rusts . . . . . . . . . . . . . . . . . . . . . . . . . . . . .47Charcoal Rot . . . . . . . . . . . . . . . . . . . . . . .47Other Stalk Rots . . . . . . . . . . . . . . . . . . . . .48Smut . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .48Ear and Kernel Rot . . . . . . . . . . . . . . . . . .48Storage Rots and Mycotoxins . . . . . . . . . .48Nematode Damage . . . . . . . . . . . . . . . . . .49Virus Diseases . . . . . . . . . . . . . . . . . . . . . .49

7 – Weed Control in Corn . . . . . . . . . . . . . . . . .51

8 – Harvesting . . . . . . . . . . . . . . . . . . . . . . . . . .65Corn Equipment . . . . . . . . . . . . . . . . . . . . .65• Corn Head . . . . . . . . . . . . . . . . . . . . . . .65• Rasp-Bar Cylinder or Threshing Rotor . .65• Counterbalance Weights . . . . . . . . . . . .65Corn Harvest Moisture . . . . . . . . . . . . . . . .65Gathering Corn . . . . . . . . . . . . . . . . . . . . . .66• Height . . . . . . . . . . . . . . . . . . . . . . . . . . .66• Synchronize Speeds . . . . . . . . . . . . . . . .66• Snapping Opening . . . . . . . . . . . . . . . . .67• Stalk Roll Spacing . . . . . . . . . . . . . . . . . .67Troubleshooting . . . . . . . . . . . . . . . . . . . . .67• Excessive Shelling at Stalk Rolls . . . . . .67• Pulling Up Stalks . . . . . . . . . . . . . . . . . . .67• Weeds, etc., Wrapping Stalk Rolls . . . . .67• Row Alignment . . . . . . . . . . . . . . . . . . . .68• Plugging . . . . . . . . . . . . . . . . . . . . . . . . .68Threshing and Separating . . . . . . . . . . . . .68Corn Quality . . . . . . . . . . . . . . . . . . . . . . . .68Field Losses . . . . . . . . . . . . . . . . . . . . . . . .69• Estimating Field Loss . . . . . . . . . . . . . . .69• Procedure . . . . . . . . . . . . . . . . . . . . . . . .69• Ear Loss . . . . . . . . . . . . . . . . . . . . . . . . .69• Kernel Loss . . . . . . . . . . . . . . . . . . . . . . .70Citations . . . . . . . . . . . . . . . . . . . . . . . . . . .72

9 – On-Farm Storage and Drying . . . . . . . . . . .73Fan Types . . . . . . . . . . . . . . . . . . . . . . . . . .74Drying Costs . . . . . . . . . . . . . . . . . . . . . . . .76Long-Term Storage Management . . . . . . .76Safety . . . . . . . . . . . . . . . . . . . . . . . . . . . . .77Additional Resources 77

10 – Grain Storage and Aflatoxin in Corn . . . .79Introduction . . . . . . . . . . . . . . . . . . . . . . . . .79What Is Aflatoxin? . . . . . . . . . . . . . . . . . . .79How Corn Is Contaminated

with Aspergillus sp. . . . . . . . . . . . . . . . .79Prevention or Reduction of

Aflatoxin in Corn . . . . . . . . . . . . . . . . . .80Grain Storage to Preserve Quality . . . . . . .81

Store Grain at Low Moisture Content . . . .81Avoid Pockets of Damp Grain . . . . . . . . . .81Avoid Moisture Migration . . . . . . . . . . . . . .82Do Not Rely on Grain Turning . . . . . . . . . .82Control Insects and Rodents . . . . . . . . . . .82Check Moisture Content During Storage . .82Check for Hot Spots During Storage . . . . .83Drying . . . . . . . . . . . . . . . . . . . . . . . . . . . . .83Equipment . . . . . . . . . . . . . . . . . . . . . . . . .83Storage Tips . . . . . . . . . . . . . . . . . . . . . . . .84Detection of Aflatoxin . . . . . . . . . . . . . . . . .85What Can Be Done with

Contaminated Grain? . . . . . . . . . . . . . .85Summary . . . . . . . . . . . . . . . . . . . . . . . . . .85

11 – Estimating Production Costfor Corn in Arkansas . . . . . . . . . . . . . . . .87

12 – Identify Hazards and Prevent Accidents . . . . . . . . . . . . . . . .89

Have a Plan to Reduce Hazards . . . . . . . .89Field . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .89Traffic and Road Transport . . . . . . . . . . . .90General Precautions . . . . . . . . . . . . . . . . .91Irrigation . . . . . . . . . . . . . . . . . . . . . . . . . . .91Grain Drying . . . . . . . . . . . . . . . . . . . . . . . .92OSHA . . . . . . . . . . . . . . . . . . . . . . . . . . . . .93Summary . . . . . . . . . . . . . . . . . . . . . . . . . .94Contacts that May Prove Helpful . . . . . . . .94

13 – Renewable Energy . . . . . . . . . . . . . . . . . . .95Corn Products . . . . . . . . . . . . . . . . . . . . . .95Ethanol Information . . . . . . . . . . . . . . . . . .95• Consumer Benefits . . . . . . . . . . . . . . . . .95• Taxpayer Benefits . . . . . . . . . . . . . . . . . .95• Economic Benefits . . . . . . . . . . . . . . . . .96• Agricultural Benefits . . . . . . . . . . . . . . . .96• Energy/Trade Benefits . . . . . . . . . . . . . .96• Environmental Benefits . . . . . . . . . . . . . .97