On Tuesday, April 25, 2017 at 5:01:23 PM UTC-5, Gramps' shop wrote:
I came into 5 slabs of nicely splayed wormy Willow, freshly cut a month ago.

Freshly cut, aye? Keep an eye out for more worm activity. If small holes (not channels) it may be powder post beetles (treat PPBs with Timbor). If it's other larvae, you might have to fumigate the wood.

*I've fumed small boards with gasoline... don't pour it on the wood. Put the gas in a small container next to the boards and cover with tarp type material.... but not in your basement. Takes about 2 days of fuming, for the gas fumes to drive off the bugs. *Pouring gasoline onto the boards will leave a gasoline smell on and in the boards for (almost) forever.

Just keep an eye out for more insects, since the wood is freshly cut. Maybe the miller has some info about the (previous?) bugs. The latest hickory I had milled, grubs were coming out as we sawed the boards.

I see coffee tables in their future. Slabs are 2 to 3 inches thick. Will be stored in dry basement. I am thinking 18 months before they are ready to be worked. Any thoughts?

18 mos sounds about right. If shorter boards, 3' and shorter, (such that you are limited to how much you can cut off the ends, later), another option is to screw/attach a "bread board" onto the ends, to prevent checking. If a shorter board seems to be checking fairly significantly, then, likely, it will be, somewhat, weak along the whole length, even if you don't see a crack all along its length. The wider the board, the more significant this effect.

PS They were free!

All the mo betta!

Sonny