Grasshoppers in Oklahoma – When is an Infestation Cause for Concern?
In my last blog post (A Grasshopper Explosion), I speculated whether the recent explosion in the grasshopper population that I’ve observed at the Sequoyah National Wildlife Refuge could be considered an infestation. After doing some more digging, I wanted to provide an update on grasshopper numbers in Oklahoma and when their populations are cause for concern.
Grasshoppers are a regular summer sight in grassland habitats like prairies and range lands. But when their numbers get too high, they can become serious agricultural pests that damage crops and range lands. According to Oklahoma State University entomologists, we typically see grasshopper outbreaks in cycles of 8-10 years. The last major infestation was in 2015.
Populations are considered at outbreak levels when there are 20 or more grasshoppers per square yard on range land, or 8 or more in cropland. Infestations tend to start in concentrated hotspots and can spread rapidly under optimal weather conditions. Excessive rainfall in May and June tends to limit infestations.
This year, surveys by OSU in central and western Oklahoma are finding substantial numbers of grasshoppers, but not at levels that would be considered an outbreak on a regional scale. However, localized control may be warranted in areas with very high densities.
Steve Creek, Wildlife Photographer
- Camera: Canon EOS R5
- Lens: Canon RF 100-500 mm F4.5-7.1 L IS USM
- Location: Sequoyah National Wildlife Refuge (Oklahoma)
- Date and Time Taken: July 18, 2023 (08:19A. M.)
- Exposure Mode: Manual
- Aperture: f8
- Shutter speed: 1/800
- ISO: 640 (Auto)
- Exp. Comp.: 0
- Focal Length: 500 mm