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Wood contains two types of water. Free water which will flow from a recently felled wood if it is squeezed in a vice. Bound water which is contained within the cell walls. It is the second of these, bound water, that gives us the headache of drying wood.
The problem is that wood gives up the bound water from its end and side grain at different rates. Also wood will lose water from the surface the surface at a faster rate than from its core. The result - splits in the ends and sides. It is possible to try and compensate by painting the end of logs so that water lose is slowed down. However, this will not prevent wood splitting. It is also advisable to leaf freshly felled timber for a number of months and let it lose some of its water naturally, before sawing in planks of 100mm (4 inches) or less.

Yes thanks. I have about 30 logs of 12' long and varying diameter of
0.5 to 1'. I chainsawed the bark off from about half of the green cut
logs and those are the ones with the worst cracks. One of the logs is a
piece of old dead elm which had no bark on it and it has no cracks.
About half of the logs still have the bark on them and have no visible
cracks, at least I cannot discern cracks under the bark.
So I am guessing that on all fresh cut logs, to leave the bark on. And
perhaps if I come across a very great straight log of a hardwood that I
leave the bark on and further, I wrap plastic on bark so the water
escapes more slowly.

Another factor is that I have them in full sun, which I should have
them in shade.

Archimedes Plutonium
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whole entire Universe is just one big atom
where dots of the electron-dot-cloud are galaxies