AusBonsai

WOW thanks Steven! Thats great!

Ken, its nice to see the "Holey Ron" being used. I was away for that lesson

JayC

Asus101 wrote:there is also a method to widen the nebari use a plane once you have the spread set. Sadly though its not available online, so it gives members a chance to discredit me on the issue....

Don't Keep us in suspense
This sounds like it could be fun, More power tools and trees

Ken

"Bonsai Today" No:17 Transplanting, on page 37-38, has "26 How to achieve a spreading root base" which shows a maple (trident?) being planed on the base to encourage lateral root growth by elininating downward growing roots. It goes on to talk of using a wooden board to tie the roots down to get the flat base to later use the "Carpenter's Plane" method.

Thanks for reminding me to go back through my old Bonsai Todays and refresh my memory on this and other techniques,

JanM

Well someone at least knows how to search
Bonsai today issue whatever the one about transplanting is.... Enjoi.

I have ed the holes in flat stuff since it appeared in Bonsai Today. I have found:
Ceramic tiles are difficult to drill - many break in the process. Developing roots exert considerable pressure and will break the tile if left for more than a year.
Cement sheet is easy to drill and durable but the developing roots easily break it apart.
Aluminium or Stainless steel sheet are easy to drill, will resist the root pressure and can be reused. I have been using the same plates for about 8 years now. Most of mine are cut from old road signs purchased from the scrap metal yard - about 4mm Aluminium cut into 7 and 9 cm squares. Others are 2mm Stainless disks or square plates.

Other observations:
When planted direct into growing beds many die in late summer - the trunks have thickened and are constricted but new roots have not made it deep enough into the ground so the tree dies from lack of water in hot conditions - keep the water up to them in summer or grow for a year in pots until the roots have made it to the edges of the plates before planting out.

After reaching the edge of the plate roots dive straight down. These roots need to be cut back hard to remove the plate and to encourage further radial root ramification.

If the plate is small the benefit is lost as the trunk thickens to the diameter of the plate unless regular root pruning and arrangement is done.

When multiple seedlings are planted through a single plate it is rare for the central tree to grow fastest. May need to control the faster growing outer trees by pruning until the central trunk becomes dominant?

Just bumping a good thread

Thanks for that Steven, that saves me a whole lotta searching.

Is it ok to use fertilizer (liquid or slow release) when carrying out the above techniques. If possible would love to see photos of your results.

Yes! fertilise while growing good roots. Whatever technique you use faster growing will generally produce quicker and better results.
I'll see if I can find some photos of tridents grown through aluminium plate.

hello,

Regarding boards under the trees to get the flat bases, I use old sheets of perspex. It doesn't have to be thick, is fairly cheap if you need to buy it (i obtained old offcuts for free) drills and cuts easily and is water proof.

I also use tiles when doing large trees. I don't bother drilling these, I just wrap in a twine that will degrade over time.

AG

The rain stopped long enough to dig some tridents this afternoon so I took the opportunity to take a few photos of tridents grown through aluminium sheet. some will recognise where the aluminium sheet has come from. These were cut from scrapped road signs that I bought at the scrapyard.
Note the 'navel' where the original trunk went through the hole in the plate.
The tree is now ready to pot up if you want to start growing branches and refining or it could go back into the grow beds if the aim is a larger trunk.

It is important to note that this technique does produce wonderful flat nebari and flared trunks but not every attempt works out perfectly. There's probably some future for this one as bonsai? Another point to note is that holes in sheet metal is not the only way to grow good nebari. Here's on that did not have a plate. the scar in the centre indicates that the roots were pruned hard to remove any down pointing roots before this one was planted in the bed.
The final result is still quite acceptable.

When you prune the roots so hard do you leave any small feeder roots or does the tree grow new ones?

Hello Shibui,

As usual, great tutorial.
Thanks for your time and efforts.

Kevin

When you prune the roots so hard do you leave any small feeder roots or does the tree grow new ones?

That depends very much on the species Edward. These are trident maple. I have found that I can prune the roots on trident maples even further than in those photos and they will still grow new roots. When cutting roots on pines and other conifers I leave more and try to include some smaller feeder roots. I also leave more roots on Japanese maple (but not much more than this).
I think it depends on the resilience and 'growbackability' of the tree. Some sprout really easily so you can cut roots and branches harder. Others do not respond as well so you need to leave more roots and more on branches when pruning.
Most people seem to err on the side of caution and cut less than what is possible.
Aftercare is also important. I have the experience and facility to be able to look after these trees as they shoot and grow new roots in spring so I can be sure of success with these tridents.

shibui wrote: That depends very much on the species ...
I think it depends on the resilience and 'growbackability' of the tree. Some sprout really easily so you can cut roots and branches harder. Others do not respond as well so you need to leave more roots and more on branches when pruning.

Hi shibui, great input into this thread as usual. I was wondering what your thoughts were in relation to Chinese Elms and this technique. I know they're hardy and can take a bit, but would you go that far with root reduction on them?