- Corn Insect Pests: A Diagnostic Guide (Univ. of Missouri, Excellent, PDF - large file)
- Diagnosing Corn Production Problems in Kansas (KSU, PDF, large file)
- Quick Reference to Corn Pests (Univ. of Nebraska)
- Insects that Feed on Corn Ears (Univ. of Nebraska)
- Insects That Attack Seeds and Seedling of Field Crops (Univ. of Nebraska)
- Pictorial key for identifying some common late-instar caterpillars found on corn (Iowa State)
- Recognizing European Corn Borer Injury (Iowa State Univ.) Covers several caterpillar pests
- Field Key to Larvae in Corn (OSU, PDF)
- Cereal Aphids (Univ. of Nebraska)
- Managing Insect and Mite Pests of Texas Corn (Texas A&M)
- Pest Management Guides for Field Crops (Univ. of Nebraska)
- Insect Management for Field Corn, 2000 (Kansas State, PDF)
- Corn Insect Information (Univ. of Illinois)
- Field Crop Pest Management Circulars (Ohio State Univ.)
- Field Crop Pest Management Circulars (Iowa State)
- Insect Pests of Field Crops (Ohio State Univ.)
- Scouting Field Corn (Penn State)
- University of California Pest Management Guidelines (Univ. of California)
- Texas High Plains
- NC 205
- How a corn plant develops (Iowa State Univ., a real classic)
- Use of Cultural Practices in Crop Insect Pest Managment (Univ. of Nebraska
- Corn Growers Guidebook (Purdue and others)
- Corn Grading Procedures (Kansas State PDF)