Or, Cutter Ants, who neatly trim-off a piece of leaf and take it back to the colony.

Igteacher, I think you are right. I just ordered Monterey B.T. Organic Insecticide; it contains bacillus thuringiensis, which targets the looper but does not harm beneficial worms and caterpillars.

Thanks for the help!

Kate, I'm familiar with cutter ants. Haven't seen them, but we do have lots and lots of those tiny and pesky Argentine ants. They don't seem to eat plants, though.

Thanks.

Bt is not selective when it comes to caterpillars. However, if you apply it only to the bougainvillea, it should only affect those that feed on the bougainvillea (most likely the looper). The younger the feeders, the better the control works. Apply in the evening, and expect to need repeated applications, per instruction intervals, for control.

Will do, gyr_falcon. Thank you.

Bleu_Maples, I'm having the same thing with my new bougies (one of them in particular is more delicious than the others for some reason). Been spraying BT once a week and leaves are still disappearing as soon as they sprout. So, you have my empathy! I can't even find any loopers at night - they're so well camoflaged. Took me a long time to find one, and it was only 1/8" long! (hanging from a thread). Argh! I don't have any other suspects though.

Yes, very disheartening! I will apply BT tonight, for the first time. Haven't yet inspected the plants at night so let's see what I find.

I think I will also apply that "mix-a-few-drops-of-dawn-in-water-in-a-spray-bottle" remedy I keep hearing about, alternating with the BT.

These plants are so strong, you see them all over the place here, thriving in the wild yet when we bring them home things start to get complicated... :D

BlueSky Susan,

I just spoke with the gardener who planted my bougainvilleas. He came to inspect the plants and, other than the insect damage, they are doing fine (a month after being transplanted). He said that leaf drop is a sure sign of transplant shock but the plants eventually recuperate. Mine haven't lost leaves and the insect damage is still small. Let's just hope that BT helps your plants and mine. :)

Let's hope so! Yes, they can have some transplant shock for sure. I hope the BT works! Frustrating not being able to find the little boogers though.

So were you able to find any loopers with your flashlight?

I wasn't able to apply BT last night and tonight the Santa Ana winds are gusting hard again so it will have to wait until Monday. I'll be sure to update. If I find them I'll take a photo :).