05 May Sorghum Headworm
Sorghum Headworm & Other Pesky Things That Want To Eat Your Sorghum
As sorghum begins to head in South Texas, it is a good time to begin watching for “head worms”. Sorghum head worm (Helicoverpa zea) is also known as the corn ear worm and cotton bollworm and can be found in other crops. In intensive cropping area like South Texas, this pest can find many hosts and move between these hosts freely. Fall armyworms (Spodoptera frugiperda) and sorghum webworms (Nora sorghiella) can also cause problems in sorghum during grainfill and should be considered when scouting pests that attack sorghum grain.
With high sorghum prices, economic thresholds drop as spending the money to protect the higher priced grain becomes an easier decision. Fortunately, Texas Agrilife has developed a very simple headworm calculator. They outline the field scouting methods and then have a website that takes into account the number of worms you find and the price of grain (Figure 1).
You can find the calculator at (https://extensionentomology.tamu.edu/sorghum-headworm-calculator/)
Photo from Mississippi State University Extension (https://www.mississippi-crops.com/2015/07/28/controlling-the-headworm-complex-in-mississippi-grain-sorghum/)