From my understanding, the more angled cut is not preferable as is it creates a larger wound to compartmentalize and the water run off is of little concern with regards to decay. At least that's what I recall hearing Dr. Ed Gilman say.That is a codominant stem. There is no branch collar there. The proper cut in that instance would be to imagine a line perpendicular to the bottom end of the existing bark ridge angled up to just outside the bark ridge at the top of the ridge. As it is, there will eventually be a lot of decay happening on the side where the stem was removed.
I agree with starting just outside of the branch bark ridge and that it will vary upon tree species etc. Nature has a beautiful way of teaching when we stop and observe. I probably missinterpreted what you're trying to get across regarding the angle, I thought you were contradicting the guy that wrote the books/BMP's on tree pruning. At the end of the day, it's not an exact science and there's always exceptions to the rule.Cut one differently and come back in a year or two and see where the dead tissue is. Do this with a Red or Sugar Maple and it will tell you exactly where you should have cut.
Shigo used to preach the "Tool to make a proper cut has yet to be invented."I’m going to say while everyone’s suggestions are text book, there is no proper pruning cut for this stem. Odds are very high that it will rot out well before it has a chance to callus. There is even a valid argument to allow the callus to climb the stub
Personally in my area I diverge in two different ways when making cuts like the this. First I avoid it, but if it’s the only option I’ll leave a big ass stub and try to do my best weighing out how nature would break it and doing the least amount of harm. The end result is much like a mini habitat snag on a living tree.I regularly ponder this, esp with larger cuts.
Sorry, should’ve been more specific.So, for discussion sake, what is that a good example of?
Great picture to highlight the difficulty of a "prefect answer" in my opinion.
The near side shows where Gilman and Shigo say it should be cut. That is where most of the response growth is happening. However, it sure looks like the far side suggests if left a little taller, the tree can still "creep" over the stub like @evo described. And it shows the tree isn't compartmentalizing that before decay settles in.
Yes...this is an sample of 1 - but I'm sure we've all seen similar...and different reactions in similar circumstances.