I've tried diatomaceous earth - sprinkling it around seedlings to keep the leafcutters out. It does work somewhat, but when you water the plants or if it rains, it has to be renewed, and it really didn't work that well for me. I've had leafcutters destroy seedlings that were circled with diatomaceous earth.
Leafcutter ants leave a chemical trail to the plants they are attacking. Orange oil has a strong odor that disrupts the leaf cutter's chemical trail. You buy it in the concentrated form and dilute it, and spray it on the trail. It works fairly well, but has to be reapplied frequently, and rain will wash it away. I imagine cinnamon works the same way, by disrupting the ant's chemical trail. Orange oil concentrate might be cheaper than cinnamon. One thing that might protect small trees is Tanglefoot and tree tape. You wrap the trunk with paper tree tape, and smear the extremely sticky Tanglefoot on it. Ants are trapped in the sticky residue. You can buy diatomaceous earth for gardens, orange oil concentrate , and tanglefoot in Austin at The Natural Garder, The problem is that leafcutter ant colonies can be huge, covering an acre, and can have millions of ants, especially if you have sandy soil as we do in the Sand Hills. The tunnels are 15-20 feet deep underground, and there are many side entrances. If you disrupt one path to your plants, leafcutters will just find another. In hot weather, they work at night while you are sleeping, and the next morning your seedlings will be stripped of all their leaves. They even destroyed my onions and habanero peppers. Leafcutters don't eat the plants, they use them to grow a fungus underground, so the usual baits don't have any effect on them. I have found that following the trails to the mounds and treating the mounds with permethrin works. Permethrin is a synthetic form of pyrethrin, found in chrysanthemum flowers. It attacks the ant's respiratory system. It's not long lasting, and the directions say you can even use it on your plants, but I only use it on the mounds. We use the brand "Viper" which Callahan's Feed Store carries. I've also tried Amdro Ant Block, ( also at Callahan's ) which you apply to the mounds, and over time is supposed to eliminate them. Since last October, I haven't seen any leafcutters active in the old mounds, or in my garden. We still have lots of them active in other parts of our land. I've read that Jack Bean leaves (Canavalia ensiformis) sprinkled on leafcutter mounds will kill the leafcutter ant's fungi. I have some seeds and may try planting some Jack Beans this year. Of course the leafcutters have to haul the Jack Bean leaves into their mounds for this to work. I've also read that Sesame planted near the mounds works as well. I ordered Jack Bean seeds from www. Banana-tree.com I hope someday, A&M will find a Phorid fly parasite for Texas Leafcutter ants, as they have done for Fire Ants. From: JSSchneider1 <jsschneid...@peoplepc.com> Subject: Fw: [Texascavers] leaf-cutter ants in Mexico To: "Edie Ymail Clark" <ediecl...@ymail.com> Date: Wednesday, January 20, 2010, 9:54 PM ----- Original Message ----- From: Louise Power To: jsschneid...@peoplepc.com Sent: Tuesday, January 19, 2010 7:18 PM Subject: RE: [Texascavers] leaf-cutter ants in Mexico If you just want to make them go away and not kill them, sprinkle about a 2 or 3-inch strip of diatomaceous earth around the perimeter of your garden. If they're like other ants, they won't cross it. For them, it's like us trying to cross a large section of blades-up razorblades. If they do cross it, it abrades the carapace and they "bleed" to death. Generally, once they've seen it and a couple have tried it, they just go bother someone else. Best of all, it's non-toxic and safe for people and other living things. See the following website: http://www.dirtworks.net/Diatomaceous-Earth.html Also, try sprinkling cinnamon around smaller areas you want them to stay out of. I don't know if it's the smell or the consistency. All I know is that if I see them coming in at the window, I sprinkle some on the sill and an hour later, they're gone and don't come back. It's sort of expensive; that's why I only use it on my windowsills or in other small areas. NOTE: Do not use the kind of diatomaceous earth used in pool filters. It's heated and treated and doesn't work. I think it's also toxic. Louise ------------------------------------------------------------------------ From: jsschneid...@peoplepc.com To: texascavers@texascavers.com Date: Tue, 19 Jan 2010 17:36:06 -0600 Subject: Fw: Fw: [Texascavers] leaf-cutter ants in Mexico I used to think they were fascinating until they began to cart off most of my garden seedlings. A & M's website has some useful information on Texas Leafcutters. The only thing I have found that works is to follow their trail back to the mound, and either use Amdro Ant Block ( not just regular Amdro), or Viper ( permethrin- which is a synthetic pyrethrin). Viper works right away, and Amdro Ant Block takes a couple of weeks to work.You have to keep at it. The label says you can dust your plants with Viper, but I don't put anything directly on my vegetable garden plants, just on the ant mound.