Speaking with experience removing standing and fallen trees, Apples are notorious core rot victims. Two inches of good exterior wood can surround a foot of rotten pulp. That two inches would have been enough to support good growth in branches (but not ehough to hold up the weight of the rotted pulp). The rot of the core could have begun long ago through an untreated pruning (To protect apple saw wounds from rot they should be coated with sterile bees wax or asphalt paint) The wood rots fairly quickly so even if you have some you could trust as structurally safe to maintain as a planter, the moisture and soil would exacerbate the decaying mold growth.
Try taking a core sample in a place you'd expect to place a drainage hole if you go to the planter use. Use a 1 inch boring bit on an bit extender and an auger drill and watch the condition of the material that is drawn out. That will tell you how much good wood remains in the trunk. I worked an orchard crew in my training days that would open up the cores, clean out the rot and back fill the cavity with cement to help keep the structure strong enough to hold the weight of fruit. A post fall treatment I have used many times is to cut off the bole with a foot or two of the trunk and turn the root bole upside down and carve a mushroom head into it with a chainsaw. But if enough of the roots are remaining you could grow Ivy on them and hang planters from/under the roots (Reminiscent of apples).
If any usable wood remains of at least an inch thichness, it would have to be dried out for years like Jabeberwok's husband is doing. Apple can make some nice veneers.
Edited by mehaul (Tue Jul 17 2012 09:11 AM)
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