I have a Golden Delicious apple and a Bartlett pear growing. I have been restoring my small orchard and plan to expand it. I have thick clay soil and about 2 to 3 feet down it becomes hardpan. So, I am all set to place an order for some trees on M-111 rootstock and come across some information that says "do not plant M-111 in clay soil." The current trees are growing and are at least 15'. The Bartlett gave us a good 2+ bushells last Fall. The apple is still recovering from some pretty severe deer damage and neglect and produced a few apples. So, I know that fruit can grow here. What rootstock can I use and more important who sells heirloom varieties on that rootstock. (I don't want to restrict myself to dwarf varieties- "apple bushes" as my friend says.)

You might consider M26. Gives you a medium sided tree. 10-15 feet tall. The roots are somewhat shallow so may not mind the shallow clay. Do not use it unless the site is well drained.

The site is on a slight grade but clay retains water. Does that count as well drained? I'm a newbie where trees are concerned. I have found a great web page giving the characteristics of various rootstocks and there are only a few that are "widely adapted:' P.18, Seedling, Antonovka 313, M4 and posisbly Geneva 30. The rest either need well drained sites or need testing. I can't seem to find anyone selling heirloom, or most other cultivars for that matter, on any of these rootstocks.

The following address is the aformentioned "great web site."
http://mars.ark.com/~squeeze/roots.html

If the soil doesn't have prolonged standing water and is not mooshy then it's likely considered well drained. You should be able to walk across it without leaving noticeable footprints, even in winter.
If you want heirloom varieties on the rootstock of your choice you'll likely have to do it yourself. Look under "Coming Events" and check out the
HOS Annual Scion Exchange and Rootstock Sale, Saturday, March 5th. You can combine the rootstock and scion varieties of your choice, or have someone do it for you. What more coult you ask?

Check with Greenmantle Nursery in Garberville Ca. They will be familiar with your conditions and they have a lot of varieties.