Oct 26, 2012 – Crazy Ants – Finally A Proper Name?


What to use to treat rasberry crazy ants?


This ant has taken a wild ride, taxonomically speaking that is. Way back in the 1950's a new "crazy" ant was found in Florida and believed to be a species native to the West Indies, and thus is was dubbed the Caribbean Crazy Ant. Then, in 2002 in Texas another invading crazy ant appeared and was dubbed the Rasberry Crazy Ant after the PMP who brought it to the attention of Agricultural officials. Now, most recently, new studies have decided that these two ants are one and the same species and that it actually is a South American species with the Latin name Nylanderia fulva, and a proposed common name for it is The Tawny Crazy Ant. This decision may well change again, but as of a 2012 publication this is the latest and greatest thought. 

But, naming things does not help you in the field. Theproblem is not any immunity the ants have to current insecticides, but insteadis the sheer numbers that they occur in. They so overwhelm an area that eventhough millions may die there are millions more to take their place. One PMPreports he commonly finds them inside oak trees that have hollow interiors fromrot, and treating within this void causes major numbers of the ants to emergequickly, but hours later they are still emerging. The pesticides easily killthe ants on contact, but there are too many ants to affect them quickly. So farthese ants are still confined to the southeast from Texas to Florida, but living things have away of expanding their range. Not a lot is known about their specific biology,but it appears they have colonies with multiple queens, increasing theirpotential to replace lost workers. They nest in almost any available place,feed on both proteins and carbohydrates, and forage in wide trails of thousandsof workers.

TheUniversity of Florida and Texas A&M continue to work on developing an effective controlstrategy for this ant, but some of the standard IPM practices can be offered to atleast reduce the problems in landscapes and homes. Trimming vegetation awayfrom the exterior walls of structures reduces pathways into the home, creatingbare strips around the immediate perimeter of the foundation helps keep theants further away and maximizes the efficiency of any pesticides applied, andremoval of unnecessary clutter on the soil reduces nesting sites. Keepinglandscape plants free of pests such as aphids or scale insects reduces thehoneydew that these ants crave.

Atthis time even the universities suggest that pesticides are necessary, althoughnot the perfect answer. In some feedback from PMPs in south Florida there issome promise using synthetic pyrethroids for their repellent action, and pyrethroidsof most kinds have given some relief from the ants for several weeks. The useof these as a perimeter treatment around structures may provide a "buffer zone"that lasts for a month or longer. There also has been good kill of the antsusing the non-repellents such as Termidor or I Maxx Pro, although completeelimination of nests and colonies does not seem to be happening yet. Baitinghas met with limited success so far, even though the ants do seem to feed oncarbohydrate baits. One suggestion that was offered was the use of the newerproduct Transport GHP, which received great label expansion in early 2008, withgood uses now for ant control around the exterior of structures. This isanother of the non-repellents and may be worth giving a try. The newerTransport Mikron has also given some PMP's good results on these ants, alongwith the use of Talstar granules where labeled.

Themost up-to-date information from Texas A&M and from University of Floridatell us that the magic wand for this ant still does not exist. They suggest theuse of contact insecticides sprayed as a perimeter application aroundstructures and along trails the ants are using. This can be followed byplacement of sugar baits that are replaced regularly to keep them fresh andacceptable. Removal of all potential harborage sites on a property will help tolimit the presence of the ants, and this will be anything on the soil,including piles of landscape debris, boxes, lumber, etc. 

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