Root grafting trunk for separation to a new tree

[Poink88]

I was reading a Bonsai Focus 2009 article last week about "getting greedy" and turning one tree into 5 plants (original + 4 grafted "cuttings") and it is really neat. They grafted new foliage and root stock at various places then severed after 2 years IIRC.

What struck me is that the new root system on some are no more than what you might get from a 3" x 3" potted seedling. Foliage is similar being just that of similar sized stock. Is that sufficient for it to thrive??? I am confused because I always read here (and elsewhere) about how little we should disturb the soil/roots, one insult per year, etc...but this operation seems super drastic but I assume works (to be featured in BF).

Shouldn't we strive to graft new root stock and use this technique (if possible), rather than digging old junipers then?

Thoughts?

 

[berobinson82]

Weird. I was reading that exact article again last night.

 

[october]

Sometimes I am amazed that some trees can survive at all on their roots systems. Last year, I styled a san jose Juniper. Nothing to drastic, just got the rough shape in order and wired. A little while later, I went to slip pot it into a grow pot. When I pulled the tree out of its pot, it had almost no roots. There was a small amount of roots on one side only. Probably the amount you would find on a seedling that had grown a bit longer than the ones you were talking about. The tree was not young either. It was about 1 foot tall with a 1 1/2 - 2 inch base.

Basically, it goes back to what we horticulturally know about junipers. That is junipers really do, for the most part, survive off their foliage.

Rob

 

[Paradox]

When I pulled the tree out of its pot. it had almost no roots. There was a small amount of roots on one side only.

I had a similar shock with my scots pine the first time I repotted it. Big stubby stump, almost no roots. Had to ask myself how the thing was even surviving.

 

[october]

There is a tree in one of the Kimura books. It was a collected mass of wood, not even like a stump, but a crazy, twisted, ancient mass of wood. I don't remember the age, but it had to be a minimum of 400-500 years old. It had a little bit of foliage on it and was still alive. When Kimura inspected it for roots. It turns out there were no roots. He theorized that the tree was surviving on the stored up nutrients in the trunk.

Rob

 

[Poink88]

So why are we only allowed to reduce the roots of a Juniper nursery tree by a third or no more than half if this is the case? Some are heavily root bound or pot is filled with roots. Doesn't compute to me.

 

[Dav4]

So why are we only allowed to reduce the roots of a Juniper nursery tree by a third or no more than half if this is the case? Some are heavily root bound or pot is filled with roots. Doesn't compute to me.

There really is no hard and fast rule, but in my experience, junipers can tolerate alot of root removal without significant risk to their health. I've reduced a very large nursery grown juniper's roots by over 75% at one go...took it out of the 15 gal nursery can, sawed the bottom 1/2 off the rootball, untangled the rest, removing 50% more of what remained to get it into a training pot. The tree dropped a small amount of its foliage, but did fine down the road. I've done it with smaller stock, as well, with similar results...check out my shohin juniper threads. The key is after care...watering appropriately, misting as needed, more sun vs less, etc. If you aren't that experienced or are unsure of how to proceed, it might be better to move a bit slower.

 

[october]

So why are we only allowed to reduce the roots of a Juniper nursery tree by a third or no more than half if this is the case? Some are heavily root bound or pot is filled with roots. Doesn't compute to me.

It is just to stay of the side of caution. In almost all cases, this from my experience as well..When it comes to regular garden center or nursery material (sometimes even bonsai material), it is almost impossible to go to an appropriate size bonsai pot, right away. I do it in 2 stages. First, I go to a grow pot or a slightly oversized bonsai pot, then a couple/few years later I usually can get it into an appropriate size bonsai pot.

This is a good discussion. This brings up the very important, yet often not mentioned, practice of how a bonsai's training begins from the root ball up. Sometimes you will encounter a tree that will make a beautiful bonsai. However, due to the roots, it can never be in an appropriate size bonsai pot or it will take a good 5-10 years to get it to the appropriate bonsai pot.

Rob

 

[TheSteve]

So why are we only allowed to reduce the roots of a Juniper nursery tree by a third or no more than half if this is the case? Some are heavily root bound or pot is filled with roots. Doesn't compute to me.

Are you sure you aren't confusing this reduction with foliage reduction? you shouldn't remove more than 30-50% of foliage from a juniper but I've never really heard this number aimed at the roots.

 

[Poink88]

Are you sure you aren't confusing this reduction with foliage reduction? you shouldn't remove more than 30-50% of foliage from a juniper but I've never really heard this number aimed at the roots.

I am a total juni newbie so I am not sure but know that I read this a lot. Maybe others are confusing pine to juni (and vice versa) when giving advise?

I am trying to learn as I am starting with juni now. Unlike broad leaf where I have lots of experience working on before...juni and pine is totally new territory to me.

Here is one from Bonsai4Me http://www.bonsai4me.com/SpeciesGuide/Juniperus.html
"Never bare-root a Juniper or change more than a third of the soil (or at very most half) in any one repotting. "

Thank you.

 

[MidMichBonsai]

Perhaps the real question is not whether or not the tree can tolerate a reduction of 50-75% of it's roots but what is most healthy for the tree and therefore the best method?

I think often times we make the process to final bonsai quality material longer by doing things too quickly. I think the suggestion of trimming the roots by only 1/3rd is to preserve the health of the tree. I'd like to conduct an experiment along these lines but I'd bet that a juniper that was repotted down to a bonsai over 3 successive 1/3 root trimming repots would be much better off and more developed than one that has had 75% of the roots removed in one go because the latter would have to go through a recovery period and therefore would have months or even years lost.

What may seem like expediting the process may indeed slow us down.

 

[TheSteve]

I'd bet that a juniper that was repotted down to a bonsai over 3 successive 1/3 root trimming repots would be much better off and more developed than one that has had 75% of the roots removed in one go because the latter would have to go through a recovery period and therefore would have months or even years lost.

The only problem with this is the math. roots grow back. a young and vigorous tree may grow back the bulk of it's roots between repottings, thereby gaining little ground while maintaining a tree in a weakened state for far longer. This is why I dislike blanket statements. In this case we are talking about a juniper, they can live on less root than most, in another case we might be talking about a cedrus spp... in which case I'd advocate far more caution. also age of tree, climate, ability to take care of the tree after repotting, etc, all must be factored in.

 

[GrimLore]

So why are we only allowed to reduce the roots of a Juniper nursery tree by a third or no more than half if this is the case? Some are heavily root bound or pot is filled with roots. Doesn't compute to me.

My Wife can't understand it either but After saving a Thundercloud Plum form Home Depot 3 years ago it started showings signs of becoming a rather nice looking decorative. For some reason this Spring she had a decent clay 8x10x3d inch pot she wanted the tree in... It was 7 foot tall to begin with and since has been doing nice at 29-30 inches. The pot it was in was 12x12x14d. She looked rather puzzled on how to fit that root mass into the lil ctn so I went inside and got a Crosscut handsaw and cut the entire root system down small enough to JAM into the pot. My only comment was "that's gonna' need a bit of water daily" but it fit, and 3 months later it's doing great.
If we sneeze on a Juniper they seem to just plain die overnight... And it seems it does not matter what Juniper it is... Makes me wonder why they are supposed to be a good "starter" plant to be honest

 

[Poink88]

Perhaps the real question is not whether or not the tree can tolerate a reduction of 50-75% of it's roots but what is most healthy for the tree and therefore the best method?

I think often times we make the process to final bonsai quality material longer by doing things too quickly. I think the suggestion of trimming the roots by only 1/3rd is to preserve the health of the tree. I'd like to conduct an experiment along these lines but I'd bet that a juniper that was repotted down to a bonsai over 3 successive 1/3 root trimming repots would be much better off and more developed than one that has had 75% of the roots removed in one go because the latter would have to go through a recovery period and therefore would have months or even years lost.

What may seem like expediting the process may indeed slow us down.

Good point but I want to know the real story...in this case, not the best way but what the tree need to survive. Be it for collection or in the case of the article, grafting.

I hate being misled that you cannot do certain things because everyone "padded" the minimum with safety factor oodles of times through "gossip". I am all for safety factor btw.

 

[october]

It also has to do with the age of the tree. Older trees sometimes do not like having their roots messed with. That includes large reductions and also repotting frequency.

Rob