[laurelrus]

We're ready to plant some fruit trees this winter to start an orchard which we'll hopefully add to year by year but have no clue about buying the trees, how far apart to plant them, and what varieties we can combine.
We have a fairly heavy clay soil. We're looking for some screening from the road. We'd like to include eating and cooking apples and other fruit that would grow happily in a windy exposed location in Buckinghamshire.
We will have to protect the trees from being eaten by our sheep and donkeys plus wildlife as there's no fencing around the area at the moment.
We'd also like to plant some willow for our goats and other animals, if it's okay to plant them in the same area.
Any advice or recommendations would be gratefully received!

[macgro7]

Don't plant willow immediately next to the fruit trees as it will take all the nutrients away as it grows much faster.
I suggest you go to YouTube and stefan sobkowiak's permaculture orchard videos. I'm using the same methods and variety of different trees - apple, plum, sweet chestnut, sea buckthorn, saskatoon berry, quince, mulberry, blue sausage tree, strawberry tree, American persimmon, japanese bitter orange, fig, and more!

[Fleecewife]

The big fruit tree nurseries will advise which varieties are suitable for your location and site.  I would use the willow around the edge, then plant the orchard within, so the fruit trees are protected from the wind.  The willows will need to be protected from livestock and wildlife as well as the fruit trees.  Pollard or coppice the willow frequently so they don't overshadow your orchard, and you can use the trimmings for your goats, or as firewood. Perhaps reduce every third willow each year, on a rotation plan, which will keep the shelter effect without taking the whole lot down in one go.
I wouldn't be too adventurous with varieties at first, just go slow and learn what will and what will not survive on your site.  Once you've got the basics established then experiment with more exotic trees.  Top fruit is not fond of strong wind.
For protecting the trees, whatever you use will need to be taller and stronger than you imagine 


Now is the time to get planting - bare root trees establish far more easily and successfully than container grown. Use 'rootgrow' or similar mycorrhizal fungi in the planting holes, as well as the usual stuff.  Loads of advice on youtube for planting and supporting trees, as well as pruning.

[doganjo]

Be warned willow can get out of hand very quickly.  If you haven't time or inclination to chop it back two or three times a year don't plant it.