Apprentice Jorge Trak and the Trident-
I’ll keep this photo essay short on words and long on images: Jorge Trak studied repotting techniques in February. We covered a lot more trees than I show here, but this Trident was one of the better documented of those we did photograph…

Jorge beginning to uncover the top roots on this Trident maple that had been growing with great abandon in my backyard for two years. There was a 9′ leader on it. It had been ground-layered for a better nebari 2 years ago.

The roots had grown through the Anderson flat and straight through the weed barrier cloth. It took Jorge 10 minutes to cut off enough of them so he could even pick it up off the ground. Look at the top edge of the flat, which is bowed out from the power of the root system.

When we uncovered the roots near the trunk we discovered a nearly 10″ fused nebari. It was about half that 2 years ago.

Cutting off the old root system with a saw. I don’t use many power tools, but this would have taken us more than an hour I think using a hand saw.

After washing and trimming, and also thread-grafting some seedlings for roots on the left side—they are the straw-colored ones. (Washing is only necessary when doing intensive root work, and generally only on young deciduous trees like this one.)
11 Comments
Hello Mike! Your workshops look fun and quite educational 🙂 Quite the works you have going here!! Congrats!! I find your use of materials VERY intriguing… rubber sheet for dividing the top and bottom portions of the root system in the ground layer? When that same trident was repotted, did you use inked sphagnum as top mulch?? Hope you can shed some light on the reasons behind this…
Juan
hi Juan-san,
Oh, those materials are not so intriguing, it’s not a rubber sheet but a weed cloth. I’m sure it looks like rubber- rubber could work just like other impermeable things like a tile if it’s small, but if you want a larger area some kind of permeable membrane is best. I used inked and shredded live moss added to the shredded sphagnum if the pot or box is going to be on top of a bench and I’ve got to look at the thing for a year, otherwise, if it’s on the ground, I don’t bother.
That’s one nice box! And the trees are fantastic. Jorge was awesome to have at our study group. What a cool guy.
Jorge is a class act. He enjoyed the workshop—I’ll have to post some photos of that sometime…
” rubber sheet for dividing the top and bottom portions of the root system in the ground layer?” Really? I would think more like weed barrier, otherwise how woild H2O get to the lower roots?
You got it! Many types of weed barrier, even GeoDisks work.
What was he purpose of tucking sphagnum moss into te roots?
Where you put sphagnum you will get more roots. So if you have an area that is thin on roots, tuck a bit of moss in there.
Thanks Michael! Yep, I’ve tried many materials before: tile, wood, hard plastic, but as you say, weed cloth is just genius for a large area. Take care!
What is your aftercare for root development when the air layer is severed? How long do you wait before root work? Do you pick out the sphagnum?
The photos were of the root work after severing; after potting in that box with the sphagnum tucked in and soil added, it was placed in a greenhouse where it still is as I’m writing this. I think in a week or so I can take it out. The sphagnum will be left until the tree is repotted two years from now.