AusBonsai

Anyone out there have any experience digging Silver Birch? Any tips on how sensitive they are, how well they re-shoot, what kind of soil medium they prefer?

Thanks

Webos

I dug one about this time last year. It had mature bark and was about 3.5 metres tall. 15cm across the base.
I cut the root ball back a fair bit, but I did not bare-root it (although I suspect that you probably can?...best too check with someone more experienced though).
I put it in 50/50 potting mix/diatomite in a large grow pot (not bonsai pot). Upon collection I trunk chopped it to a height of about 25cm back to bare wood, and by early to mid spring it was shooting buds absolutely everywhere! It was very thirsty and grew branches very quickly. I had to continually rub off buds that I did not require. It did end up getting powdery mildew due to an exceptionally humid summer in Melb last year. I have read that the wood is quite soft and can be susceptible to rotting.
Also read that they can shed their lower branches too...although I don't have enough experience with the species to verify what I read, as it was my first dealing with siver birch.
I didn't have enough room for it where I live (as I collected other trees that had precedence over it...pines and oaks etc...) So I took it to Dad's place under his guarantee that he would look after it. He never watered it and moved it on to a concrete patio(in full sun) next to his hot water service(more heat!) where the plastic pot heated up considerably and fried the roots (as I said, he forgot to water it too!).
That combined with the powdery mildew must have weakened it beyond repair and it died. I left him with exact after care instructions which he ignored (my fault for trusting him!)
So please don't discount what I wrote before it was taken to Dads, as it would have survived even with the powdery mildew, had it been looked after accordingly...as I said, after collection it was throwing buds left right and centre and branches growing ever so fast too!...the branches grew half a metre in a couple of months!
This was my experience. Hope it helps? Check with others that have dealt with this species a lot before though.
Cheers, Dario.

Excellent write up Dario. Thanks a lot for that. i'll dig this birch and keep you informed of how I go with it. half metre in a couple of months is definitely a sign of good recovery! By the way, how hard was it to dig? How well do they root themselves in?

Thanks

Webos

Hi Webos, it was tricky to dig as it was up against a fence. The root system was quite extensive with some fairly thick tap roots. Every time I thought I had cut the last tap root, there seemed to be another, but as I said it was in a tricky position and was fairly large.
The hardest part was using a hand saw to cut through the trunk extension that was below the roots that I was keeping. This was done once it was out of the ground. If I had access to a reciprocating saw (not sure of spelling, but it is electrical),it would have been so much faster and less tiring!
Half a meter branch growth in a couple of months or so (on the highest branches-it was very apicially dominent), but that is not including the waiting period for buds to pop from a bare trunk.
If possible, trunk chop it but leave it in the ground and it will recover faster as it has access to its tap roots and no root disturbance etc...then next season dig it up. Just a thought, although it may not be practical depending on your situation?
I fed mine heavily with seasol, charlie carp and grow better pellets, but waited for buds to appear first...but initially I did use seasol for a soak and water in once potted, and then weekly until buds appeared, then combined above feeds weekly. I soaked the grow better pellets in water and applied as a liquid/organic fertilizer as well.
This was my experience, I hope others contribute so that you can get their advice too...possibly someone with much experience with this species.
There is a book by Nick Lenz called "Bonsai from the Wild" and it has a breif section on Birch as bonsai. Only a page or so of info, but interesting...do you have it?
Good luck mate! Dario.

Birch are notorious for not back budding. But that siad as Dario has found that is not the case with all variants of the species. I have had mixed results with them in my early years and have not tried again since.

They are also notorious for die back around wounds, bleeding and not healing over. I think the best way to grow them is slowly from seed. I have one I am doing that with. Slow and low.

Slow and Low that is the tempo... Well, whatever the result, worth a try as the tree is to be chopped no matter what.

That's it, slow and low, that is the tempo! I will try to get a photo when I repot, perhaps tomorrow??

Give it a bash, might get a good result from it!

Yeah not sure what species of Betula that I had my hands on, but as I said...I have not seen a tree back bud so prolificly!
Amongst other things I think that Nick Lenz may write something that might go like this in his book Bonsai from the Wild..".Birch is a difficult species to grow as bonsai, they readily die back when collected to begin anew. Even if the trunk does not die back the branches will.
Small trees with immature bark take a lifetime to whiten up under bonsai cultivation. Birch perform better in a leaner soil of medium particle size and an inorganic content of 40% or less.
Pruning can present problems: large scars will heal over in time, but the callous is somewhat bumpy and retains immature black bark for many years. Removal of large branches may lead to trunk dieback in the vicinity. The suggestion is to jin large branches slated for removal. Hollowing out birch trunks is rarely a good idea because the wood is soft and rots quickly, telling the tree that it is time to sacrifice itself for fresh and undamaged basal suckers.
Birch prefer richer fertilization than many deciduous species. When fertilized moderately they die back more readily. Always pinch back the vigorous shoots at th etop when they achive two or three nodes, even if you are growing the birch out. Let the smaller branches lower down develop. It keeps them alive. Birch are sensitive to slight environmental differences and each bonsai growers yard is a different environment..."
Hope I don't get in trouble and that this info helps you Webos?
Some great things are also said about birch too! Don't treat the above info as gospel...go for it and best of luck!!
Dario.