Highest production temperate fruit/nut trees

I am trying to figure out good low/zero work fruit and nut trees to help feed my future pigs. I know black walnuts can produce 6000 pounds per acre, but take 20 years to get to that production and are very hard nuts. I also know apples can produce 40 tons here, but that's with intensive farming. White sapote are supposed to be the highest producing fruit trees but they are sub tropical at best and I am in Canada.

I am wondering what your best producing trees are (zones 3-6 hardy)?

All input welcome.

There were some very big "standard" size pear trees where I used to live in zone 4b.  And they dropped tons of pears.  Standard apples grown in a permaculture way don't need to be intensive.  I've heard chestnuts could be good for pigs but I'm not sure if they'd be any better than walnuts.

Mulberries grow fast and produce massive amounts of berries--though only for a few weeks in the summer. They also provide dense shade, which might be good for pigs.

dunstan chestnuts are definitely on the list as they likely are the most the fastest per acre and good for fat gain and flavor. mulberries produce a lot of fruit yes, but total calorie and weight is probably lower than apples, but i will def consider growing one in the pigs pen as collecting them from the ground would be a pain

so far my plan currently is ill be growing productive apples, black walnut and dunstan chestnut in an acre or two, and grow sweet crabapples, sargent hybrid oaks (1000lb acorns a year) and illinois everbearing mulberry in the pens for them to forage. honestly i doubt theres anything that will produce better per tree than sargent hybrid oaks, but per acre apples and pears probably would...

anyone know really good producing apple varieties?

I'd say plant apple varieties that you would like to eat or process.  By the time you have trees and pigs and whatever else, you probably won't use your time to optimize your apple crop, so I don't think that any differences in yield will be anything but theoretical.

good points timothy, i was wondering if theres any trees out there with minimal pruning/spraying that have huge yields. ill probably end up with antanovka apples, as they are super hardy, versatile and i can plant them true to see so no need to buy 20-50 grafted trees that will just end up in a hogs belly

I'd plant as many varieties as possible.  It will help protect from early/late frosts and disease if you plant a range of different apples - early/late flowering/fruiting etc.  crab apples are good for pollination, varieties that keep well are useful in winter and cider apples are good for...cider!

The highest production tree is actually an invasive in my region, the Autumn Olive. Just North of me in Southern Illinois they populate into the hundreds of thousands of trees. They produce gallons and gallons of delicious fruit. They also fix nitrogen. So, they make excellent nurse trees.

I would also recommend pears and walnuts as they produce copious amounts of fruits and nuts. The highest production shrub/cane I would recommend blackberries/raspberries depending on where you live. The warmer it is the better blackberries do, and vice versa. Blueberries also have a really nice neglect factor like the rest of what I mentioned. As long as the soil is acidic (4.5 to 5.5), they'll grow in nutritionally poor soils.

As far as apples go, it just depends if you have issues with coddling moth. If you don't then you can plant cultivars like Liberty, Macfree, Freedom, and William's Pride. We grow Liberty and have no disease issues whatsoever, but coddling moth is devastating here. So, we have to micromanage it unfortunately. Same with plums and peaches in our area with plum curculio.