Tree pruning guidance

Asked May 28, 2020, 2:33 PM EDT

We planted a swamp white oak the past November. It’s starting to get lopsided as the tallest branch seems to be coming off of the main trunk. Since we planted it less than a year ago, I figured I’d wait a little bit to prune it this winter. I’m concerned though because with a little moderate rain today, the tree was almost bent in half from the weight. Any suggestions? Thank you!

Baltimore County Maryland

2 Responses

The tree seems to have a leader which is not dominant - instead, a main side branch or two seems to be out-pacing it in growth. To prevent this from becoming a structural issue in the future, corrective pruning should probably be done sooner rather than later. You could wait until winter to do this, but if summer rainstorms are likely to continue to weigh-down the branch as badly, perhaps now is best.

We have attached a photo with a line drawn across the branch in the area you should consider pruning. Use sharp pruners and try to snip just above a node (a joint, often where leaves emerge). In this way, you will be left with minimal dead wood as a stub. Clip it straight across so the surface area is smallest and can seal faster. Typically, we would not recommend removing this high a proportion of its canopy, but the window for formative pruning, when it would have been less impactful, has passed. Given how long you have had the tree, ideally this would have been corrected while the tree was younger and still at the nursery.

The ties on this tree are too tight; they should be looser and allow the tree to sway several inches in any direction. This not only triggers the formation of anchoring roots but also development of taper to the trunk, which helps to stabilize the tree. Make sure the ties wrapping around the trunk are padded with a non-abrasive material to avoid damage to the thin bark. Felt or foam pipe insulation can both work. After about six to twelve months of staking, trees rarely benefit from keeping the stakes in place. If the staking hasn't stabilized a tree in that period, it isn't working. You can give it another six months from now if the ties are loosened since that will truly be the start of its stabilization period.

Miri

Apologies - the incorrect photo was attached. Here is the correct version with the yellow line drawn on it.