I've been told the small caterpillars I'm seeing in my yard are armyworms. They're eating my bermuda and I don't want them getting to my fescue. What's your best spray or is there a granule that's better?
Armyworms can appear throughout the summer months and can damage most any southern turfgrass. Though they prefer St. Augustine, bermuda, ryegrass and bluegrass, they'll readily attack most any fescue or bent grass turf when foraging. They also eat plants, flowers and basically anything green and low lying in the yard they find. Distributed throughout the United States in most any state that has decent moisture and green lawns, armyworms release 2-3 waves of larvae per season. Starting in the south, larvae feed, pupate and emerge as a moth that tends to fly north where it will mate, lay eggs and start the cycle all over again. Females can lay hundreds of eggs so a yard can go from none to a lot seemingly overnight. When conditions are right, there can be huge migrations of this pest across the southeast and up toward the Canadian border.
Armyworms damage grass by eating it's crown or grass blades. They'll create or weave webs across your turf in small areas which are easiest to see if viewed in early morning when the dew is still wet. During the day the larvae will hide amongst the thatch or in self made tunnels just below the soils surface. Anyone that leaves grass clippings to mulch back as fertilizer is creating a haven for many insects including armyworms. They love this environment. If you've been leaving your clippings or if you note a lot of loose thatch throughout your yard, get it cleaned up. This will help by both eliminating their nest sites and allowing treatments to work better after being applied.
Though it's common to see small damaged areas, armyworms will scatter throughout your turf so it's important to treat the whole yard. Many times the damage they cause will denude or brown patches in the grass. This damage can be misdiagnosed as a fungus since the end result is similar looking. But if you're seeing the adult moths or young caterpillars and are sure you have activity, get treating to reduce long term damage.
The strongest treatment option includes a combination of BIFEN GRANULES and CYONARA. Apply the granules first at the rate of 1.15 lb's per 1000 sq/ft of turf. Do this 2-3 times per year. Bifen granules work well on most any pest and it's a good idea to use them a few times a year whether you have armyworms or not. In fact, simply applying them 3 times a year will probably prevent armyworms from ever getting established in your turf. But once they're active, it will require a 1-2 punch to knock them out for good. After applying granules, spray over the top with the Cyonara using a HOSE END SPRAYER. Use .5 oz of product for every 1000 sq/ft of turf. We also have CYONARA RTS which basically is the same product but ready-to-spray. In theory you should only have to spray 1-2 to knock out the current infestation and then apply granules periodically to prevent future problems.
Organic options would be applied the same. Instead of Bifen Granules, use the ECO GRANULES. They too should be applied throughout the year to prevent pests and if you use them 3-4 times (quarterly), you'll help keep most any common pest under control in the yard. Once the granules are applied, spray over the top using ECO IC or BUG PATROL. The ECO is a concentrate and you'll need the Hose End Sprayer to apply it; the Bug Patrol comes with it's own sprayer and is ready-to-spray.
Here are direct links to the information and products listed above:
Cyonara Concentrate: http://www.bugspray.com/item/cyonara_ec.html
Hose End Sprayer: http://www.bugspraycart.com/equipment/sprayers/gilmour-6g-385
Cyonara RTS: http://www.bugspray.com/item/cyonara_rts.html