Hey Mirai People,
Just wanted to share an air layer success story in case the technique can help anyone:
I can’t remember which stream I heard it on but Ryan mentioned leaving an air layer exposed for about a week after you strip the bark instead of wrapping with wet sphagnum and plastic right away. I believe this lets the xylem dry out and reduces the chance that the tree will try to heal instead of producing root tissue at the air layer site. So I tried it this year. I’ve tried to air layer several trees each year for the past 4 years with inconsistent success across various species of deciduous and evergreen. This year I tried three different trees: A weeping cherry, a red maple, and a river birch. I removed a stripped of bark about the same height as the branch diameter and left it exposed for 7-10 days before wrapping it with damp sphagnum/plastic. Didn’t see any activity for a few weeks and didn’t water myself but they did get watered by the rain 3-4 times. I checked all of them yesterday and there’s a full ring of root nodules and no attempts at re-healing on all three! So, basically it worked like a charm and I just wanted to share my success and recommend the technique of leaving them exposed for about a week before wrapping. I only have a few years of experience with air layers but I have never seen this level of success or close to it. Of course, your timing may vary for cutting the air layers in the first place depending on your climate/region.
I didn’t keep any detailed notes, but to my knowledge leaving them exposed was the only difference in my technique. I’ll try to remember to update this thread with notes on how they progress but for starters they’re all doing amazing!