Eventually I would. Seems funny, but those lower limbs will never be any higher on the trunk. They would make the tree nice and easy to climb, but not to mow under. Probably would be a good idea to prune the smaller limb on the V also and let the branching begin on the main leader.

The decision is whether to do it this year or later in the life of the tree. It is advised that the tree develop a strong trunk before pruning side branches as they are contributing to the growth of the trunk, so I would say wait until the tree is older.

"The lateral branches growing on the sides contribute to the development of a sturdy well-tapered trunk. It is important to leave some of these lateral branches in place, even though they may be pruned out later. These branches, known as temporary branches, also help protect the trunk from sun and mechanical injury. Temporary branches should be kept short enough not to be an obstruction or compete with selected permanent branches."

I might, however, elect to take of the weaker branch of the Y. Perhaps others will contribute their knowledge to this question.

How neat you planted it from seed. How old is the tree?

Here is a link that might be useful: Tree pruning information ...

Thanks for the advise roselee. I gathered the acorn in Fall of 2005, just before we moved in to our house. It germinated in a small pot, then a year or two later I planted it in the back yard. Its doubled in height each year so far, so eventually it should grow into a majestic shade tree.

Overall I agree Roselee especially about the y at the top. The lower laterals can stay for a period of time. A good rule of thumb to remember as to when to cut these lower limbs is at an inch in diameter a branch will never show on the trunk later on. This also means that it will heal quickly and well. The best degrees of angle of branching coming from the trunk is more than 45 and less then 75 degrees. This provides the strongest attachment of heartwood and will resist wind and ice loads better than angles less or more than these. 60 degrees would be considered optimum. Hope this gives some help for now and later as you make more shape choices.
Happy Growing David

roselee gave you some good advice, but I'm going to tell you what I would do.

It looks like the tree has developed a good trunk and I would prune the lower branches and the smaller one at the V. If you prune them now, the wounds will be small and start to heal. I have a rule for trees in my yard, no bending over to mow.

Why do you have the tee caged? cats? kids?, someting else?

Personally, I would leave it for now. Especially after the hard winter we have had.

Reasons for Pruning

To train the plant

To maintain plant health

To improve the quality of flowers, fruit, foliage or stems

To restrict growth

Too much pruning can put a tree in stress. You might want to check out what TAMU has to suggest.

Thanks for the advise, all. The fence around the tree is to keep out rabbits. They knawed off the top 1" of the tree a couple years back, luckily it came back ok.

Put me down in the "prune it now" camp.

I'd concentrate on trying to train a central leader. It light not even hurt to try and stake and straighten the main stem while its small and pliable.

Sure, it'll look like a sad little twig temporarily, but in the long haul it's best for the development of the tree IMO.

I am in Northern Alberta with a mature Bur Oak that is over 35 years old, tall and Majestic with lots of acorns ( and unfortunately lots of destructive squirrels attracted to it). I have pruned over the early years and my rule was to take only one branch a year until the lowest branch was the lowest you want as a permanent branch. For me, about 6-7/feet up the main trunk. This causes less stress to the tree and allows it to have healthy growth.