Sunday, June 22, 2008

Leaf Cutter Ants

Leaf cutter ants on a piece of rope--from Wikipedia.

Normally, I don't work on Sundays unless there's an emergency.  This morning, while walking the dogs, I finally found what I was looking for--on plants that had been losing their leaves, I finally saw leaf cutter ants.  I had looked for nests but in the grass it's hard and leaf cutters can go impressive distances. 

Leaf cutter ants fall well within my definition of emergency.  I've been really worried about 2 young  papaya plants and a small Chinese hat plant, all of which are trying to make it and all of which have been under attack.

After breakfast, I hauled out my handy-dandy industrial strength sprayer and my small hand pump of Hormitex, a very specific, really excellent ant killer in powder form.  Many people use bait that they lay along the trails so that the ants will take it back to the nests, but I put nothing down on the ground that the dogs can pick up.  Ethel and Fred are Labs and they will eat rocks, I swear, if they thought it was any kind of food.  Lucy is a little better, but not by much.

I waited patiently (well, for me) until I could identify the column of ants and then started tracking it back to the nest.  When I did find it, it was conservatively 60 ft away; I've seen trails much longer than that.  That is the danger with leaf cutters--they don't even have to be on your property.

Fortunately I found the nest, but in doing so, I was amazed to see that the ants had cut--actually cut--narrow tracks through the grass down to the soil that resemble in miniature superhighways.  Sure enough, you should see the little red monsters truck right along!  It should not be surprising, however, because they have mandibles that vibrate a thousand times a second to saw off pieces of foliage.  I have seen a small bougainvillea stripped overnight; I've read that some species of leaf cutters can strip a small citrus tree overnight, which is pretty impressive.

Their nests are huge underground chambers that can measure 45 ft in diameter and be 15 feet deep, containing as many as 8 million ants, all after my papaya trees!

No.  Not without a fight.

A standard way of dealing with them is to locate the nest, plug up all the entrances except one, and then insert the tube of your pump powder sprayer as far as you can.  You tamp dirt around the hose then pump powder into the nest.  Given the size of the underground chamber, you pump a lot.  I did what I could this morning with not just one but two nests, because I'm almost out of Hormitex.  Have to get some tomorrow.  It may not have killed all of them, but I'm hoping it has given them pause, because I was really appalled with the numbers swarming over my best papaya.  I sprayed that plant and around its base with Arribo, hoping to give the poor plant a breathing space until some of the other measures take hold.  I've fertilized the papayas, trying to give them a boost for recovery.

And just to keep reminding me of who is really boss of the planet, I ran across yet another column of nomadic army ants.  Looking for something else, I didn't notice that I had walked right into the column until I felt this nasty bite on my leg, and looked down.  Hey, brothers and sisters, no problema, have it all your way--and while you're at it, could I invite you over in this direction where there are 8 million snacks waiting for you?


sunshine said...

Hi Joyce,

those ants look like real mean critters!

I haven't seen you around in several days, hope everything is ok.



Joyce said...

Hi, Will!

Yep, I'm fine--just celebrating my birthday a week late, since I was sick last week. A good friend is here from Volcan for a few days, and we've been having a great time, talking. things are good--just no time for a blog.

The leaf cutter ants are BIG ants! They're harmless to humans and other animals but ye gods can they devastate plants in a hurry! I actually had to kill off two more nests, but the reward is that the plants that had been stripped of leaves are already making a comeback.


sunshine said...

Hi Joyce, great to hear that you are better. I hadn't seen a new blog in a few days and I hoped everything was ok. I also had sent you an email a few days ago from my new address.....had been wondering about pet regulations re importing an animal.

Good to hear that you and your friend are having a good time. Yes, those ants sure look like they could do a lot of damage to plants in a very quick time. We have nothing like that. Slugs used to be a problem for a few months in spring/summer, but only on big green leafy plants like hostas e.g.

All my very best.

Joyce said...

Hi, Will--I didn't get any email from you about your new address. Please resend.