Split Wood At Branch Attachment Showing Decay

Love these photos and images of the inside of wood.  It always surprises me how symmetrical the two halves of split wood can be.  Its never deliberate to "get the wood" to split this way but it must say something about weak points in the wood for it to keep happening.  And my splitting maul.....

Callous wood

Both sides.  The outside of a hole or old pruning scar, the inside showing what is normally not seen

Callous wood - Inside View