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rudy de haas
08-31-2014, 4:39 PM
hi:

Assuming the photo I tried to attach is attached.. (The color is "enhanced" to show contrast).

This is a piece of jatoba just cut on a table saw (I don't have a band saw).. There are no marks on the exterior, and there's nothing wrong with the
saw blade. I cut about 40 feet after this, and this is the only example.

The deepest and longest one is about 1/16th deep, but two of the shorter ones appear to match up on opposite sides of the saw blade - 1/8th thick.

But...? what are these? Anyone know?

More importantly, this wood is supposedly kiln dried and has been in storage for at least six months. Is there any risk I'm bring live worms (or whatever) into the house with it?

peter gagliardi
08-31-2014, 5:35 PM
I believe they are worm or beetle holes. I don't know where you are located, but if that was imported to the US, it has to pass certain very strict protocol in order to cross over. I think a high heat treatment, and /or a fumigation type treatment. In any case whatever made probably did so while the tree was living, and are gone now. Very few pests can work their magic on kiln dried wood.

Bradley Gray
08-31-2014, 8:01 PM
Here in the midwest powder post beetles will occasionally show up in kiln dried wood but always leave little piles of wood powder. If you haven't seen the dust you are good to go. Jatoba is insect resistant:

Rot Resistance: (http://www.wood-database.com/wood-articles/wood-durability/) Jatoba is rated as being very durable in regards to rot resistance, and is also resistant to termites and most other insects. (Though it has been reported to be susceptible to attack from marine borers.) from wood-database.com

Wayne Jolly
09-01-2014, 3:48 PM
Just for my own curiosity, do bugs alway bore holes that are perpendicular to the wood grain, and perfectly straight? And in the case of the board on the right, in line with each other? I don;t have too much experience with bugs (except the termites that have eaten my redwood fence posts), but the ones in the picture just look too straight and uniform.

Wayne

rudy de haas
09-01-2014, 4:35 PM
No dust piles - but the holes showed up after cutting on a table saw, so I would not have been likely to see them had they been there.

rudy de haas
09-01-2014, 4:43 PM
I don't know.

A quick google image search did not show any comparable insect holes - the majority are not straight, go along with the grain if made during growth and
across grain with an exterior point of origin if made in dead wood, and/or form the holes in a honeycomb like structure left in the wood. These have no point
of entry that I could see, appear to go straight, and are generally almost horizontal with respect to the standing tree, I could imagine a bug making these
as the tree grew with the entry point being filled in after the bug left or died, but if the tree was growing when the damage stopped, why didn't the holes fill in?

David Helm
09-01-2014, 5:41 PM
Lyctids (aka powder post beetles) can reinfest kiln dried wood. They especially like hardwoods. There have been a number of imported hardwood flooring products that have brought them in to this country. Kiln drying, if not hot enough or long enough will not kill them.

David Helm
09-01-2014, 5:43 PM
After reading my post I realized that it may sound like they haven't been here before. Sorry if I implied that.

Danny Hamsley
09-01-2014, 10:00 PM
Those holes were made by ambrosia beetles. The black lined tunnels are distinctive because the beetle brings in a fungus on its body, and the black lining is from the fungus. They usually attack dying or dead trees, or logs that have been felled but not yet sawn. They can get in a log in only a few days after it is felled, and they are a nuisance on log yards at sawmills. The good thing is that they cannot live in dry wood, and as the wood begins to dry out, they leave. By the time your wood was kiln dried or heat treated, they were long gone. They are harmless, except for the holes they leave behind.

295932295933

Above is a rustic kitchen island that I made from white oak. In the close-up pic of the top, you can see ambrosia beetle holes.

Dan Hintz
09-02-2014, 6:36 AM
Those holes were made by ambrosia beetles.

I don't think so... there's zero staining around those holes.


Rudy, I can't tell what they are from the pictures (do you have a close-up?), but it doesn't look like bug bores. They are entirely too perfect for that. Is there any chance your blade picked up detritus, like small stones, and pulled them into the cut?

ken masoumi
09-02-2014, 7:02 AM
Ambrosia beetles could in fact have made those holes ! although it is hard to believe considering how straight the grooves are:

https://encrypted-tbn2.gstatic.com/images?q=tbn:ANd9GcSGgJk_BCiFOBzB7zmhkXTKBgOrC7BP0 WN2qJOJgQv1z5ypn28o
https://encrypted-tbn3.gstatic.com/images?q=tbn:ANd9GcRp4AsIRbaT2Ou4GSS27c7Nukh1oKolR X1RYmnipxrVyW8HaphHPA

rudy de haas
09-02-2014, 10:14 AM
"Rudy, I can't tell what they are from the pictures (do you have a close-up?), but it doesn't look like bug bores. They are entirely too perfect for that. Is there any chance your blade picked up detritus, like small stones, and pulled them into the cut? "

My first thought too, but I don't think so - nothing there but the sawdust the saw was making. My camera is quite old - and close-ups aren't in its repetoire.

---
Correction: the camera can do close-ups - I just checked the manual - it was high end when I bought it (1999). However, those boards have now been planed so I can't do it even if I could :)

Danny Hamsley
09-02-2014, 9:31 PM
It is the inner wall of the bettle tunnel that is stained by the fungus, not the surrounding wood.

Dan Hintz
09-03-2014, 6:23 AM
It is the inner wall of the bettle tunnel that is stained by the fungus, not the surrounding wood.

Every piece of ambrosia Maple I have (probably a thousand pounds +) looks like this:
296026
The bore is a tiny fraction of the stained area. If it's not stained, there was no fungus introduced...

Danny Hamsley
09-03-2014, 7:36 AM
Dan,

Now I understand what you are referring to. We are talking about two different effects. Ambrosia beetles bore into living soft maple trees, and they do not kill the tree. The tree is not weak, stressed, or dying. The fungal flame in ambrosia maple is a combination of the fungal growth and the tree's reaction to the fungus. It is not common to see this type of ambrosia beetle and fungal effect in living trees other than these maples. Most all other living, healthy trees repel the beetle if the beetle tries to attack them.

However, when ambrosia beetles attack a dying or dead tree like an oak, they overcome the tree's defenses, and the fungal presence is only seen in the lining of the beetle tunnel, which turns black. There is not a fungal flame streak like in ambrosia maple. There is also not any frass (chewed up sawdust and beetle poop) in the tunnel. Powderpost beetle tunnels are not black lined, and the tunnels are filled with frass.

Dan Hintz
09-03-2014, 11:15 AM
however, when ambrosia beetles attack a dying or dead tree like an oak, they overcome the tree's defenses, and the fungal presence is only seen in the lining of the beetle tunnel, which turns black. There is not a fungal flame streak like in ambrosia maple. There is also not any frass (chewed up sawdust and beetle poop) in the tunnel. Powderpost beetle tunnels are not black lined, and the tunnels are filled with frass.

. T. I. L....... :)