When you see Fall Armyworms, don’t delay!
A couple of years ago I received a call from a friend of mine who told me that his lawn was moving around and he didn’t know what was going on. Puzzled by the phrase “moving around”, I told him I would come by and take a look at it for him. Upon arrival I finally understood what he meant by it, as his lawn was being attacked by a hoard of fall armyworms. The fall armyworm feeds on bermuda, fescue, rye, and bluegrasses, and, as the name suggests, they tend to appear in very large groups. So much so, that a bad infestation of them can eat an entire football field worth of grass in just 2-3 days! Fall armyworms are highly susceptible to cold temperatures, but in the years where winter temperatures are mild, the number of them that end up surviving tends to spike. As the year gradually continues to warm the armyworms begin making their way north from the southern region of the country, feeding on various turf grass as they go.
The turf damage comes from the larvae form of this insect right before it burrows itself into the soil and later emerges as an armyworm moth. The moths will emerge in 10-14 days and begin to mate, where females can lay upwards of 1000 eggs before the life cycle begins again. Multiple generations of this insect are produced every single year and with a new crop appearing every 2-3 weeks they move north in a hurry. The damage caused by these insects begins appearing as the young larvae feed on the chlorophyll at the tips of the grass blades causing those blades to brown. As the larvae age the damage progresses down the blade until all is consumed and the grass as dead. Bermuda grass is typically capable of recovering from this damage due to its ability to reproduce from above ground stolon growth, but clumping grasses like fescue and rye generally do not recover from aggressive infestations.
It is important to be on the lookout for these pests as we approach the end of the summer months, and to let us know right away if you are seeing damage. The good news is that we will happily come out get the lawn treated for you here at AgriLawn, but it is crucial to get them under control before the damage becomes too wide spread. If you choose to treat for them yourself there are several products that are listed for the control of armyworms, with both synthetic and organic options available. As always, you need to read the label of any product before you purchase it and make sure that the pest you are trying to eradicate is listed on the label. Follow all label directions when applying the product and check to see how long the effectiveness of the active ingredient will remain before you have to reapply it.