Lightning struck white oak

[OzarkChris]

One of our neighbors has a very large oak tree (60ish' high, 40+" at base and some of the branches are 20+" at the tree) that got hit by lightning and blew off all of the bark - it is still standing but the leaves are turning brown & dying. He asked if I wanted it because it would be to hard to split for firewood. The tree looks fine (except for it missing most of its bark) and the lightning didn't cause any visible splits, cracks, etc. I've never cut lightning struck wood with my CSM before and obviously havent cut any on my new bandsaw mill.

I know there are superstitions that go along with them trees and many folk won't even cut them down but I still have a few questions concerning this tree.

First, my understanding of why the bark gets "blown off" is because the sap gets superheated and literally explodes forcing the bark off the cambium and/or the sapwood. With this in mind, and if he is right that the wood will be very hard, will the wood be worth the wear & tear on the mill? 

If the lightning superheated the sap enough to explode, does the sap throughout the tree turn into something like epoxy that will dull any blade it sees?

Any suggestions on how to proceed?

I didn't take any pictures of the tree but it's just up the street a piece so next time I'm around I'll take some and post.

[Magicman]

I would not hesitate to saw it.  The bark being blown off indicates, to me, that the lightening affected the outside and not the core.

Limbs ain't logs so I would concentrate my efforts on the main stem.

[Digger Don]

I was going to say that I had no idea how to answer your question, but couldn't wait to see what others had to say. Magicman jumped in before I could get it typed. I'll believe whatever he says and wait to hear from others. Don

[Magicman]

It's a shot in the dark and the only loss is the time spent.  To me the potential reward exceeds all else.  Old saying; "Nothing ventured, nothing gained".

[Southside]

I have sawn logs from one Poplar lightning strike tree.  I happened to watch it get hit on my own place so I was hoping for some magic pattern with a unique story.  Instead I ended up with a lot of stress in the log, Poplar can have plenty, but this was more than usual.  Parts of the log were bone dry, some was honeycombed and split, some was just lumber.  I would try it again with a different species if I had the opportunity to see if the results are different or not, never know if you don't try.  

[beenthere]

Think you can go ahead and saw it up, and it won't be any different than any other "normal" tree. And then, you can tell us how it acted any different if'n it does.  8)

The MM knows.. 

[OzarkChris]

Thanks to all for your responses! This winter when we cut it down (too busy this time of year with hay & cows),  I'll take some pics and post as I attempt to mill it.

Magicman (or others), you mentioned that limbs are not logs. Are limbs not good to mill? Why?

[OzarkChris]

Limbs ain't logs so I would concentrate my efforts on the main stem.

I hope this doesn't post twice.
Could you please explain? Should I not mill limbs? Why?

[TroyC]

I'm no authority here but I think you will find the limbs have tension/compression stress which make your boards turn to firewood real quick. Even trunks have stress sometimes. I can't see it in a trunk but I think a lot of the more experienced sawyers here can look at a perfectly straight log and tell you how it is stressed. I have to cut and when the board jumps up I say "OOPS!"

[Magicman]

Logs (trees) grow vertical and support a fairly even load so they will generally saw without stress issues.  A leaner or an edge tree with all/most of the limbs on one side will almost always have stress issues.

Trees that have a "Y" fork generally saw OK, but those are still the main trunk, not limbs.

Limbs spend their entire life growing horizontal and supporting a very uneven load.  The stress energy is stored within the limb in order for it to do it's job and when you saw you release this energy.  Depending upon which face you open the boards may crook, curl, or make a propeller. 

Even then all logs are individuals unto themselves, so give it a shot.  You may find something nice, or produce designer firewood.  Either way, you win. 

[mudfarmer]

First tree my lt15 sawed was big lightning hit white pine, it did have a big split and had blown out a piece about 2x6x10 from the butt. It is all siding now   saw it up!

[OzarkChris]

Many thanks Magic. That makes all the sense in the world!