According to the responses you entered, this is likely the pest you are dealing with. To confirm this, use the positive identification section. There are two species of caterpillars that are whorlworms in sorghum. It is important to identify the species in your field to make the right management decision because each species is impacted by different pesticides.
Helicoverpa zea (aka the corn earworm or cotton bollworm)
Spodoptera frugiperda (the fall armyworm)
Bollworm: Caterpillars will have a light head capsule and their bodies are covered with small bristles that can be observed with a hand lens.
Fall Armyworm: Caterpillars have a dark head capsule and a ‘Y’ shaped suture on the front of its head. The fall armyworm also has dorsal lines lengthwise on the body.
Other Important Hosts
Cotton (bolls), Corn (ears), Sorghum Head
Scouting and Thresholds:
Bollworm: Pyrethroid insecticides should provide satisfactory suppression of bollworm on sorghum.
Fall Armyworm: Don’t use a pyrethroid to control fall armyworm. Consider an alternative class of insecticide (there are several) to manage fall armyworm or a mixed population of headworm.
Although we tried to include the most significant pests related to sorghum our tool cannot help you identify every insect found on sorghum. This tool is built to inform you of the most common and significant pests of sorghum in Texas. If the insect you are dealing with does not match the description above then talk to your extension agent or visit this page to look at all the different important potential pest associated with each part and growth stage of sorghum.