I support the main trunk just below the first branches or higher if there is a good tie off point. A T post pounded about 2ft into soil and positioned a few inches from the trunk has never failed to keep mine upright.

I been wondering about this myself.

Semi dwarf trees are about 15' tall.

I don't believe you need to support dwarf trees with wire if you prune it in one of the forms with short branches and use a length of electric conduit to support the trunk.

Short branches aren't created by stubbing them but by removing branches more than a third diameter of the trunk and leaving everything else. The lesser diametered branches fruit almost immediately and I believe there is a cycling in and out of branches but I don't manage any trees this way so am unsure of the details.

My local U pick trains the dwarf apple trees on a tall trellis, for better picking. I believe they get the trees very cheaply, so they went with the dwarf route as opposed to semi dwarf.

Most commercial growers are going with dwarfs these days, although the cost of trees adds up when you need double or more the quantity. Labor is hard to come by and expensive.

Labor in all aspects of management is greatly reduced with low growing trees that don't push out a lot of vegetative growth. Even commercial orchards have to pay a premium price for skilled pruners and it probably takes a third the time to prune an acre of dwarfs over semi-standard free standing trees.

Squirrels, coons and deer also prefer dwarfs, though.

Tall spindle dwarf trees. Easy to pick and you can train just about anyone to prune them. My free standing dwarf trees are much more of a pain to figure out pruning. And don't get me started on Liberty apple trees.

Does anyone have a photo or a link to a photo of dwarf trees supported I am thinking of doing this too.

Orchardman:

U of MN has a listing thru their extension site about staking
dwarf apples. They list 3 choices:

-individually stake each tree

-stake each with conduit but top of conduit
must be fastened to a wire strung down
tree row for support.

-run 2-3 wires down tree row and stake
trees to the wire (almost like growing
grapes).

I hope you can find this document on the internet. I have
seen orchards in SW WI stake each tree with a metal fence
stake.

Here in SE WI, we have several orchards growing apples
on M9 or selection of M9 that grow their trees on wire.

Greetings again:

Here is a second shot from another local orchard.