annie Hatfield

When I was in Morocco, I frequently saw sheep grazing the olive orchards, but there was usually a shepherd there too.  One this to remember is that cherry leaves, especially wilted ones are not only lethal to horses but according to sheep-people around here, to sheep and goats too.

IF your septic system is functioning approrpriately[i][/i] emphasis on if, the leachage should be clean enough to drink.  but would you?  same for the plants that would grow from it. the folks at the health dept say that it shouldn't be done because of the chance of contamination.  and that ol' e coli and other bacteria perking in there could kill you. So, while it's understandable that you hate to wast the moisture, the risk probably isn't worth it, simply because you may not know you're system's not working right till it's too late.  tree roots will definitely damage your field as will animals grazing on it.  do you have a curtain drain around it?  try trees on the other side of that.

Some additional thoughts:  what is the Prenn method of water supply?  I've not heard of it and can't find anything googling it.  more on water: we have a cistern and will only use the water for flushing toilets and washing, not for consumption. also, most surface water, even if it's a new pond is not safe to drink in the area due to agricultural runoff, mine contamination, acid rain and local septic runoff as another poster mentioned.  you're going to need some sort of water treatment system, either a sand filter or r.o. if you don't have a well, and even with a well, the water is full of iron and manganese and where it is not it's full of lime, really mess up the plumbing in no time.  With all your new plantings, you are going to need a LOT of water to keep them alive and you just can't depend on rainfall in Ohio.  This spring and June were one of the wettest on record but the past few years we've had drought conditions one year and record floods the next. 
seasons for planting trees, if they're bare root like mail order, plant in the spring.  balled and burlaped or potted from a nursery can be planted just about any time but conventional wisdom says in the fall so the roots get established over the winter.  you still have to water them though, especially since Ohio falls tend to be dry.  but if you plant in the fall  be sure to protect from the deer who love new young trees to nibble when the other browse is gone. or even before!  if you're off grid what are you doing for power?  What kind of house are you going to build?  just curious.  We have electricity but a big generator for when the power goes out which it does frequently in the country for some reason.  love to hear how it's going and share some experiences!

Have you checked with the local colleges or universities?  Maybe they have pilot programs or test areas that they would be interested in talking about?  My son worked for the center for applied ecology out of his univeristy after he graduated so I know they exist.

Just joined up and reading the post.  Are you from the area originally?  This was an unusually dry late summer, though not actually a drought. How was the water situation?  I live in the Southern Appalachia area of Ohio and I guarantee that it will get below -5 in the winter, if we're lucky only once or twice but there have been times when the high did not reach 0 for days on end.  There have also been very mild winters where it barely got or stayed below freezing although I can't remember many of those. 
As for fruit, we have had a lot of luck with blueberries and currents, gooseberries, raspberries, pears, cherries (every other year it seems) and apples.  The heritage types seem to do the best but I had some lovely yellow delicious and winesap this year.  I planted the trees several years running, some in spring some in summer or fall, depending on when I saw what I wanted.  I can't say one did better than the other with the exception of the very first ones I planted before there were people on the site.  I planted in the fall and the deer killed them all by rubbing.  The apple and cherry tree I planted on the south slope (before I learned that they were supposed to be planted on the north slope) have been more productive than the ones on the north slope.  Interested to know how it's proceeding.