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Corn Insects

All Corn Insects Content

aerial view of South Dakota farm and surrounding land

Pest & Crop Newsletter

SDSU Extension publishes the South Dakota Pest & Crop Newsletter to provide growers, producers, crop consultants, and others involved in crop production with timely news pertinent to management of pests, diseases, and weeds in South Dakota.

Green leaf with two yellow spider mites with dark spots.

Dry Conditions Are Ideal for Spider Mite Activity

Several counties in South Dakota are experiencing dryer than normal conditions, therefore, it is important to monitor crops for spider mites, as they thrive during periods of dry weather.

A pasture containing a mixture of grasses and alfalfa.

Start Scouting for Grasshopper Activity in Crops and Grasslands

Most of Eastern South Dakota is experiencing very low grasshopper populations. However, this is not the case for many areas in Central and Western South Dakota.

Left: Bird cherry oat aphids. Right: English grain aphids.

Aphid Populations Are Starting to Show up in Corn

Small populations of aphids are starting to show up in corn fields, which could be problematic if the populations continue to grow. During dry seasons, they can have a greater impact on corn.

Grain storage bin.

Steps to Prevent Stored Grain Infestations

As wheat harvest is underway it is important to ensure that grain bins are prepared in the best possible manner to prevent insect infestations. There are seven steps that can be taken to help reduce the chances of having infested grain.

Top: Tan caterpillar with dark brown head on corn stalk. Bottom: Black caterpillar with light stripes and yellow-brown head capsule. Caterpillar also has small spines on body segments.

Caterpillars Active in South Dakota Corn Fields

Both European corn borer (Ostrinia nubilalis) and corn earworm (Helicoverpa zea) are active in corn fields. Sometimes the caterpillar activity and identity of these two species can be confused.

Eight green beetles in a row in the top half of the image and a row of seven yellow beetles with varying black stripes in the bottom half of the image.

Corn Rootworm Adults Are Active in South Dakota

Last week, we noticed the emergence of northern corn rootworm adults in South Dakota. The adults of both the northern and western corn rootworms generally emerge in mid-July and remain active until the first hard frost.

Brown moth with light markings present on a green leaf.

Western Bean Cutworm Moths Observed in South Dakota

Over the weekend, South Dakota experienced strong southerly winds, which brought warm temperatures to the state. In addition, these winds also brought insect pests north, which included moths of the western bean cutworm.

Sunny field with large puffy clouds and blue sky

2020 South Dakota Pest Management Guides Released

August 25, 2020

The 2020 South Dakota Pest Management Guides are now available for free on the SDSU Extension website.

corn field with sunrise in the background

Best Management Practices for Corn Production

iGrow Corn is your unbiased, research-based guide to corn production, providing the latest recommendations to help increase yield, reduce input costs and protect your investment.