Adds a 2nd comment here since was helpful too. So, spring of 2023 and I began to worry if cutting the competing leader last fall was correct. I knew I read 3 years back when planting my 20 young Arborvitae emerald greens, now 5 to 6 feet tall, that if 2 leaders were allowed they likely split due to heavy snow. Well cleaning the interiors and spraying Neem oil on the stress areas having black blight I began to think I was wrong in cutting. Thank you, I see that my cut was exactly as you did, I also see the offshoot I have yet to cut and targeting is as you showed too. Feels better and will cut another tree’s competing leader this fall. Btw, all my trees are really full and healthy, but... I live in N. Idaho near Montana and the wet high mountain climate does contain its issues that keep’s my guard up.
