Skip to main content

Tar Spot

Shriveled yellow corn kernel with a pinched base held between two fingers, showing poor fill and stress-related kernel development issues.

December 3, 2025

Disappointing Corn Yields in 2025

By Tom Hoegemeyer - Former Adjunct Professor of Practice, Roger Elmore - Emeritus Extension Cropping Systems Agronomist, Eric Hunt - Agricultural Meteorology and Climate Resilience Extension Educator, Bob Nielsen - Professor Emeritus, Purdue University , Jenny Brhel - Extension Educator

Hero graphic showing three photos of corn leaves with southern rust, tar spot, and Goss’s wilt symptoms over a red cornfield background.

August 22, 2025

Corn Disease Pressure Builds in Nebraska

By Tamra Jackson-Ziems - Extension Plant Pathologist

photo collage of tar spot map behind corn leaf and text about what's included in article

June 20, 2025

Early Tar Spot Detected in Nebraska Corn; Irrigation Shown to Elevate Disease Risk

By Talon Mues - Extension Educator, Saleh Taghvaeian - Biological Systems Engineering Associate Professor, Dylan Mangel - Extension Plant Pathologist, Tamra Jackson-Ziems - Extension Plant Pathologist

Tar spot on corn

October 13, 2022

Tar Spot Disease of Corn Spreading to More Nebraska Counties

By Tamra Jackson-Ziems - Extension Plant Pathologist, Kyle Broderick - Extension Educator and Coordinator of the UNL Plant and Pest Diagnostic Clinic

cropwatch graphic

March 19, 2020

What’s New in Plant Pathology

By Tamra Jackson-Ziems - Extension Plant Pathologist

Tar spot on corn

October 21, 2021

Tar Spot Disease of Corn Confirmed in Several Nebraska Counties

By Tamra Jackson-Ziems - Extension Plant Pathologist, Kyle Broderick - Extension Educator and Coordinator of the UNL Plant and Pest Diagnostic Clinic

N Field banner

July 6, 2023

This Week on N Field: Tar Spot in Corn

July 12, 2024

This Week on N Field: Tar Spot 2024

Closeup of black spots on corn leaf

July 12, 2024

Corn Diseases Developing in Some Fields — What To Watch

By Tamra Jackson-Ziems - Extension Plant Pathologist

Extension educator county map

July 26, 2024

Extension Crop and Pest Reports (July 22-26)

Tar spot symptoms on corn leaf

August 15, 2024

Corn Disease Update: Fungicide Expectations for Disease Control

By Tamra Jackson-Ziems - Extension Plant Pathologist, Jenny Brhel - Extension Educator

Tar spot on corn leaf

August 29, 2024

Black Spots in Corn? Southern Rust, Tar Spot and More

By Tamra Jackson-Ziems - Extension Plant Pathologist, Kyle Broderick - Extension Educator and Coordinator of the UNL Plant and Pest Diagnostic Clinic