COVER STORY
The 2021 Invasion of the Fall Armyworm in the U.S. By Dr. J. Kevin Mathias Retired Turfgrass Instructor and Advisor University of Maryland Institute of Applied Agriculture
IN
2021 unprecedented damage from the fall armyworm occurred in numerous areas of the U.S. including locations in Maryland, Pennsylvania, and Virginia. Many turfgrass managers struggled with the severity and the speed with which the damage occurred to their facilities or their clients’ lawns. The goal of this article is to provide information about the fall armyworm and what we might expect in 2022. I have been involved in consulting work with a new sod producer in central Virginia over the past two years. I visited his facility on August 17, 2021 to inspect his fields and to discuss weed control options for the coming fall and spring months.
During this visit, the tall fescue-Kentucky bluegrass fields were in good condition and showed no damage from any type of pest. However, I received a panicked phone call on Sunday, August 22 to ask if I could come by on Monday to take a look at a field that was turning brown. During my inspection, there were large areas in one of the production fields that had severe brown patch damage. As I was showing the classic brown patch lesion to the owner, we also started to find small (1st to 3rd instar larvae) and very active caterpillars that were present in other areas of the field. I had never seen the fall armyworm caterpillar during my 38 years as an entomologist and instructor at UMD and I was at first taken aback as to what type of caterpillar we were looking at. I knew it was not a cutworm or sod webworm caterpillar and through a process of elimination came up with an armyworm. Since the caterpillars were quite small, I was not able to identify it as the fall armyworm until I had an older specimen that had the classic markings of fall armyworms.
PHOTO 1: The photo is of 6th instar fall armyworm caterpillars illustrating the inverted “Y” mark on the head, 4 dots in a rectangular shape on the last abdominal segment, dark bands on both sides of the body, and 4 dots arranged in a trapeze formation on each abdominal segment.
12
MTC TURF NEWS
