Sure - You can safely remove at least the bottom 4 branches right now. In late summer maybe take a couple more bottom branches. Next spring take more until your lowest branches are at least 4-5 feet above ground level = Done with the low branches.
Yes - they are one in the same. It is just a given that we all know we want our lowest branches 4-5 above ground level so they are going to be removed - no questions asked.
The upper lateral branches are a little more complicated as you want to balance the weight of the branches (and the load of fruit) sort of equally around the tree - N-E-S-W, and you don't really want them too close together. This may take a few years until you get the look you want, but certainly on the day you plant the tree you can easily look at it and see what you want to remove for starters....like maybe the smaller ones, those that maybe have 2 or more branches growing in the same direction and relatively close together, those that would want to compete with the main leader. But the bottom line is that 4, 5 or 6 lateral scaffold branches is plenty for one tree. Believe me you will get lots of branching from the main scaffolds once they get bigger.
Here are maybe 5 or 6 main saffolds but they have plenty of other branches growing out from them...
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The key is to not crowd the tree too much. You do need to have good air flow and sunlight throughout the tree.
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I planted these Red Wealthy's in the spring of 2018. Here they are in the fall of 2020 - a little over 3 years later. Bottom branches are all gone and most of the unwanted laterals are also gone.
And, yes - I should not have allowed that much fruit to grow on such a young tree - My Bad.
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The other issue you should deal with early on is proper crotch angles so that the lateral scaffolds have enough backbone to support heavy loads of fruit. You can cut spreaders out of lath and put them in place to encourage the proper crotch angle (45-60 degrees). Once they start growing in the right direction these can be removed - usually within a year.
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You can cut the back 1/3 - 1/2 initially. As the tree grows you will also want to head them back so the tree doesn't grow so tall that you can't maintain it (12' is plenty high for me). You don't want the laterals growing out too far either as the longer they are, the weaker they become to support heavy fruit loads. Some say you should remove up to 1/3 of the lateral growth per year as well. I usually just try to judge it by looking them over when I am doing annual pruning.
Obviously, I let this one get too long...although thinning the fruit would have helped also... If you have to support a scaffold branch with a 2X4 - it is too long.
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This is what too long of a scaffold branch and/or too much fruit can do if you allow it.
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Hope the photos help out some.