Pruning a Young Japanese Flowering Cherry Kwanzan Tree
Dear Tree Expert,
Our tree is about 2-3 years old. Not sure how old when purchased, but was planted in Spring 2011. It has never been pruned. Using my textbook from HORT 100, I have pruned 4-5 branches from the tree. One was the lowest sitting branch; the rest were competing branches. I read that for every 10' of tree height, scaffold branches should be spaced 6" apart. The tree is about 10' tall. However, it seems like the tree is too young to space scaffold branches 6" apart. If I were to do that, I wouldn't have many branches left. I've attached pictures to give an idea of the problem. In the middle of the tree, there is a cluster of branches. These are not co-dominant trunks. There is a main trunk that grows beyond this cluster. In fact, the trunk split into two branches - so I DID have a co-dominant trunk further up - but I removed one this year. What should I do about the cluster of branches in the middle of the tree? Should I wait until the tree matures another 1-2 years? Even so, how should I prune....how many branches should I remove?
Arapahoe County Colorado
Thank you for providing photographs.
I would not be in a rush to prune a lot of the branches on your Kwanzan cherry because the tree is still fairly immature and you have already pruned quite a bit. However, it was probably a good idea to remove the co-dominant trunk to encourage a strong leader. You will want to maintain that strong leader for about 2/3 of the tree's height at maturity.
Of course, always prune off any crossing or rubbing branches and any water sprouts. This should be done in late winter or early spring.
This is a decurrent tree, meaning that it has a more oval shape rather than an upright or pyramidal shape that has a strong central leader up to the top of the tree. While your tree is not technically a shade tree, it doesn't bear fruit, so I am attaching some information on proper pruning of shade trees, which should answer your questions.
I noticed in your second photograph it appears there are several small branches that have been removed, and it looks like small stubs are remaining. These should always be pruned off so the tree will have the ability to heal over those areas, thereby preventing insects or disease from invading the tree. (One is on the far left branch and the other is on the right side of the picture.)
Some information on proper pruning techniques:
Thank you for your response, suggestions, and site links. A lot of the info in the site links can be found verbatim in the HORT 100 textbook that I have. So, what I cannot find in this literature is what I'm hoping you can address. I understand that you're saying not to prune the tree anymore than I already have. And I will not. However, I am wondering what to do in the future, as the tree grows & matures, about the confluence of branches in the bottom half of tree. Should I be concerned, or should I let the branches grow as they are?
PS. You observed in the photos some pruning cuts that I did not make. I really hadn't noticed them until you brought it to me attention (!) so, obviously the tree was pruned at some point before I came along. Thanks for catching that, and I have pruned the stubs.
I have looked at a number of Kwanzan Cherry articles online and I think the photographs of your tree and the configuration of branches extending from the central trunk reflect the characteristic shape of that particular type of tree. I don't think there is anything to be concerned about and it would be best to just enjoy watching it grow, giving it a little attention each spring if you see some dead, crossing or rubbing branches.
Below is a link to an article that illustrates the shape of a mature Kwanzan. Your tree looks to me as though it is definitely developing into the expected shape of a Kwanzan.
Also note on page 2 of the link that it mentions a single leader should be encouraged and little pruning is needed on this tree.
I hope this is helpful to you. Enjoy your tree!
Oh, thank you. Funny enough, I had that exact thought as I was looking at another (more mature) tree in the back yard that also has a confluence of branches. I thought, that tree seems to be doing fine; maybe there are trees that just grow that way.
Thanks again for all your research and advice.