OK we signed on our house this past August (YAY!!!) and can start thinking permanent structures and vegetation. The very poor and so not to scale drawing of our backyard/Urbstead with chicken yard is what I need help with. You can obviously see that a good portion is for the girls, the hot pink spot is the resident mulberry tree, the pink box is my future strawberry patch (where the girls can get some berries) the big purple box is my future blueberry bush in an above ground planter cause I'd need a back hoe to dig a big enough hole to create an acidic soil, the bluish dot is my husbands yew bush, dark green is the trunk of our soon to be trimmed maple tree, big red blob is the fire pit (gotta love wood ash!) and the pale green box is going to be my straw bale greens bed. Note I did not have the space to include my south facing side yard which will have my big straw bale veggie garden. I go into all this detail because I need some advice. I want to get some rasp/blackberry canes into the picture and still have a backyard for my son to play in and my dog to have her space. Plus a clothesline is in the works. I know big ambitions for a rather small yard. I would also appreciate advice from fellow Missouri zone 6 gardeners as to what varieties of blue, straw, rasp, and blackberries have worked here. I probably won't get canes till next season but it would be nice to have the planning in the works. After we get a fence up I'm going to espalier some fruit trees too.
In season when mulberries are ripening, the first place my chickens go when I let them out in the morning is to check under the mulberry tree for any that fell overnight. If a mulberry is ripening ion a low hanging branch they will jump straight up to get it. It's hilarious to watch. If you haven't built the chicken run yet you might consider building it around the mulberry tree.
I'm not quite in your zone, right on the border of 6 & 7, but the local master gardeners recommend Ozark Beauty strawberry if you want an ever-bearing variety. I've been happy with Cardinal, which is a June-bearing.
We are going to get ontop of the shed this spring when it's all sappy and try to rearrange the branches so they fall in the chicken yard. We've had it up for about a year now (molting freeloaders). We planned on doing both June-bearing and everbearing so we had the big crop for preserving and the long season to use for fresh eating
When I was a kid my dad built a clothesline that was retractable. It was 4 or 5 lines wide and mom could pull it out and attach it to a post on laundry day, then it could be put back when we were using the patio. This was in a small yard at a house we lived in for 4 years, and I was old enough to be aware of how handy it was, but too young to understand just how dad built it.
That could be a space multi tasker, freeing up play area when you aren't hanging clothes out.
Can't help with varieties of berries, but I think your espalier idea is a great one!
Your chickens are going to love that mulberry tree! And they will keep the area cleaned up for you, since mulberries can be so messy.
Blueberries adapt better than you might think. They are very shallow rooted, so you don't have to dig deep to amend, other than they like a well-draining soil with some humus to it. You can use garden sulfur to adjust your pH easily (take the pH of your existing soil and apply according to directions). I only have to add it every couple of years. Mulch them heavily with a wood chip mulch and they should be very happy. If you have hardpan soil or a low wet spot, you may be ahead to do a raised bed though.
Not sure the scale of your drawing, but you'll want to make sure your fire pit is well away from your trees, since the heat rising can scorch them.
I recommend Ozark Beauty (everbearing) and Sparkle (June-bearing) strawberries for their good disease resistance. The U-picks plant several different varieties to extend the season. Heritage is a dependable raspberry. I have Blueray, Bluecrop, Patriot and Northland blueberries. They are a little different in their fruit size, ripening times and growth habits, with Patriot and Bluecrop being my favorites, but you'll want at least 2 varieties for good pollination which yields bigger berries. Your ag extension agent will have info (or see if you can find your ag extension's website) for what varieties do best in your area. Some areas have different disease pressures, although you and I are nearly in the same hardiness zone.
The fire pit is actually a good 7-8 ft from the tree. We love and hate the tree, the only reason it's getting severely trimmed rather than yanked out is our yard would be unbearable without its shade. My soil is extremely rocky and the only reason the flower beds are somewhat ok is I've been working them for two years now (yay for rent to own now!) and at one point there was a swimming pool where our pit is so we have sand everywhere under the tree, made it a good place for a fit pit.
I don't pinch back but enjoy them the first year. With the hot dry summers we sometimes have mine don't always come through the summers in good shape. Some winters can be pretty hard on them too.
I know you are supposed to pinch them back, that makes them "better". But I don't always do what I'm supposed to do, to me good enough is good enough even if it is not always best.