Somebody needs to attach images of this. I suspect that it is not a problem at all but, as Jean says, aerial root initials. A picture would solve the mystery in a nanosecond.

Darn it when things aren't as we'd like! But, it's not a stupid plant. It needs love, too. I would consider cutting it back. Could turn out to be your favorite plant ever. Now, time to head on over to some of the plumeria seller websites and pick out one you'd like to have. I may just do the same!

OK, the pictures are good. I would definitely pull the cutting to look at the stem below soil level. If there is rot, cut back to white wood, let it sit in the dark for a week or so, wet the stem end and add Rootone or other rooting/cloning compound with fungicide, repot and water once. Another test you could also do is to use a pin and puncture the branches to see if latex flows from the hole. If so, the branch is still alive. If not, it may be dead. The white, pithy stuff at the tips is the core of the branch. The presence of bugs in the core is not a good sign. I would recut the tips to white wood, but at a 45* angle. Then apply a layer of latex caulk to seal the cut end. This will keep water and bugs out of the tips. Since you have no growth tips on the plant, it is essentially a "center" cutting, and will take longer to root and produce leaves. Be patient. You won't get claws on this plant since it has no tips. New growth will appear at the sides of the cut tips. Look for small "bumps" anywhere from the tip down about an inch or two at an old leaf scar. This will tell you the plant is recovering and should survive. I would clear the pea gravel away from the stem so it doesn't touch the stem. The gravel can get hot in the sun and burn the stem, killing the plant. If the soil gets very dry, you can dig a moat around the edge of the pot and add a little water around the edge, staying away from the stem itself. What you are trying to do is add moisture without getting the stem wet. Good Luck. Let us know what happens.

Can anyone help diagnose and treat my tall, ten-year-old plumeria trees? The main trunk and branches have deep wounds that appear to start as dry, splitting bark. My beloved plumeria began as two small sticks , which sprouted for me and faithfully bloom year after year. I keep them indoors from mid-Sept. through late May because oof Minnesota's terrible winters. I treat them lovingly all winter long as they fight spider mites and dryness. Usually they thrive once they are taken outdoors to fresh air and saunshine. BUT not this year - they have very tiny leaves and wounds all over their branches. THANK YOU.