So the bottom limbs are at about 5 ft?

If so I would hold off for now to see what kind of angle the lower limbs grow at. If they stay horizontal you will probably have to cut them...but they may grow up to 7 or 8 feet before leveling off. There's no need to get in too much of a hurry. Remember that you can always prune them if you decide that they are too low, but you can't put them back if you prune them off :)

Yes, you should not prune a young tree too much too soon. But, yes, you are right to be thinking about this now and asking the question. Here, in some detail is how I would plan to prune your tree.

First, I would do nothing for at least two years--the tree needs all its branches now to help the tree grow stronger. If you prune it up too much now you have a skinny tree that will not develop its roots very fast, and will not develop a strong trunk. The present branching structure looks very good.

But you should begin to think about how high you want to prune this tree eventually. From the picture, I see two good possibilities. If you want to have the tree eventually pruned up to about 7 feet, I would look at the first of two sets of larger branches as your target. About 2 ½ feet higher there is another set of strong branches. If you want to have that be the eventual height of the first branch, you can plan for that now.

What I do with my young red maples, and I now have seven, is make sure that no branch below the eventual height of the lowest branch grows more than about two inches in diameter. If I have a lower branch that seems to be getting too large, but I am not ready to prune it off (remember I want the tree to grow strong), I will shorten it back to some good secondary branch to slow its growth and help it develop a good branch collar prior to finally pruning it off 1 to 3 years later.

With your tree, if you want the higher set of branches to be the eventual lowest branch, you donÂt want the set of branches lower down to get too large. They are nowhere near too large now, but if they get to be 1 ½ inches in diameter you may want to shorten them as described above, prior to finally pruning them off later.

All of the smaller branches below and between these two sets of larger branches should be left for now. Perhaps the lower ones--those below 7 feet could be pruned off in 2 or maybe better 3 years.

--Spruce