What caused this?

[fishki]

I made a scrounge run on some county burn piles and pulled out some decent size oaks,
started splitting and then this happened.

I'm sure something happened during the life of this tree to cause this, but not sure what it would be.
I had 9 rounds about 24" diameter and they all were like this.

 

[Poindexter]

Cant say for sure but i have seen this before.

Do you care enough to count the growth rings and figure out what year the tree was insulted?

When i was in boston in 03 they were still measuring against hurricane Carol (1954)...

My guess is whatever year that was was dry or cold or wet so the annual rings of that year and the year to follow are especially close together.

 

[lost in the woods]

we always called that ring shake. . . it can be really prolific in hemlock. . . the old timers always said that trees growin up on the ridgetop would be ''shook'' (from the wind?)

 

[CincyBurner]

+1 for ring shake
I recall seeing it in hemlock (the stereotypical example) and oak. Those in forest products industry would have a good idea of the incidence of occurrence.
Some literature describes it is caused by disease (bacterial root transmission) https://blog.spib.org/shakes-checks-and-splits-in-dimension-lumber/
while some literature cites a physiological cause - (broken link removed to http://www.wsl.ch/info/mitarbeitende/fonti/PF_2002_Trees_16_8__519-522.pdf)
Perhaps dependent on species whether disease or physiological ?
http://ir.library.oregonstate.edu/xmlui/bitstream/handle/1957/5302/Splits_Cracks_Wood_ocr.pdf

 

[TheAardvark]

Makes it easier to split....

 

[Captain Hornet]

I had a bunch of big Hickory do that. The rounds were about 4 foot across and every round did it. Don't know why.

 

[pernox]

I just got through a bunch of red maple that had a similar effect. The heart was like its own small tree that the rest of the tree grew around, complete with branch nubs and everything. Funny thing, it was a three stemmed tree (big sucker!) And this only occurred on one stem.

 

[blacksmithden]

I just cut up some lodge pole pine that was doing that. It was standing dead wood. I wouldn't guess how long ago the trees died, but it looked like at some time, a forest fire went through. Most of the bark was long gone, and there was barely noticeable charring on the outside of the bare wood. I don't know if the inner/outer trunk separation was caused when the tree was alive or dead, but it looks exactly like that. Sorry..not much help here.