Bark Buckling Beetles Killing Trees

[brahmburgers]

There's a yucky type of tree killer that's slowly spreading around my 6 rai piece up here in Chiang Rai. It usually starts at the soil line and works up, though in one tree it started up high and worked its way down. The resulting tree and branches wind up very light, as though they've been sucked dry.

It seriously blisters the bark to where you can peel toast-sized chunks away with your hand. Under the blistered bark is a sort of reddish-brown jelly. I don't think it's one organism alone, but rather a combination of beetle grubs and specialty worms.

It's not specific to one species, but will attack several types of trees. I did some tree surgery today and found at least two types of worms. One was small and white, the other (more common) was reddish brown, about 3/16" wide by just over an inch long. they're squirmy and quick. There are often some ants around, though ants are everywhere - however it may be some symbiosis, with ants protecting the worms and grubs. A large 20" diameter tree was killed in a short time, and a some large and impressively colored beetles were involved - with bodies as long as a Swiss army knife.

On the live tree today, I scraped with a trowel to get as much loose bark and jelly off, then applied copious quantities of a soap/bleach mix - brushing it in with a stiff plastic brush. I also cleaned around the base of the 1.5' diameter tree and found several types of little black beetles. I have a feeling my RX will work - as the tree still has most of its healthy bark. It's a handsome tree with blond bark - plus it's leaning over my house, so it would be a big deal if it fell.

I know it's generally good to keep tree trunks from getting too much direct sun - especially when they're young. I've tried painting lower trunks white - and it may help a bit. In the States you can buy white plastic surled strips especially for that. However, some of the trees that are infected at my land are in shaded areas. The concoction to slather on the exposed bark might benefit from having tobacco or cayenne pepper mixed in, but I didn't have those things handy today, and I wanted to get to dealing with it right away.

suggestions appreciated.

[meandwi]

Sounds to me like you have tree bores, or fruit borers. It is a larve of a moth that attacks the weak part of a tree, lays it's eggs, and the larve dig into the bark and trunk sucking it dry. The reddish brown jelly is probably the sap coming out of a bore hole. this will cause other insects to hide under the damaged bark and feed on the sap and or the larve poop.

Look around the base of the tree and see if you notice a fine sawdust. If you see it? you have bores. Now you have a serious problem! The best way to get rid of them is to keep the trees healthy. Fertilize and prune to promote new growth. Use a systemic pesticide rather than a spray. Spray will help kill the beetles and other bugs that are hiding under the bark but not the bores.

Google, Lepidopterous fruit borers. You will find more info about them.

I have seen this bore in many types of trees, mostly on fruit trees. Very difficult, but possible to kill.

Hope you save them,

meandwi

[brahmburgers]

Thanks meandwi. The larger tree which died and was felled had large diameter holes (about the size of a bar girl's index finger) with beetle grubs within. Also had hard white fungi growing in places. Both the grubs and the fungi were edible - at least by Laos friends who came by to harvest them. As mentioned earlier, it seems to be a combination of insects and worms, and infestations appear to vary from tree to tree - at least on the five or so on my land that have the buckling bark.

One has the bits of sawdust at its base, others don't. I agree also that doing everything to keep the trees healthy is paramount - including watering, and fertilizing. Not sure whether mulch would help or not, as it might harbor the baddies - maybe better to keep the soil scraped around the trunk. On the other hand, trees like mulch as it keeps their surface roots moist.