Hi,
Pls, help with my podo!
The last year the tree was in substrate akadama, grit and pumice, unfortunately in december I noticed the mould. I treated the whole tree with insecticide and acaricide. The podo was indoor in the winter, these days I repoted again in new fancy substrate for conifers ( akadama, pumice, kiriu etc) .
In my place was freezing these days and I put indoor the podo. And again the mould is present, so when the tree is inddor the mould is existing, when is outdoor - not.
Sorry for my poor English.
Regards,

Why did you use insecticide and acaricide? Non of them have any affect on mold.

Good point!
I went to agro pharmacy near me and they gave me explanation that I need acaricide for the treatment.
So on the picture above is mould or mites?

Its mold. I would use a tooth brush and gently brush it off.

Thank you.
I remember in December when the podo was inside I removed the first layer but in a few days the mold appeared again.
Probably I should try some fungicide or to repot in a few months before the winter and then applying the fungicide on the roots? The podo is inside all the winter.

I dont think your tree is healthy and mold is not the reason. Its just eating dead parts of the tree. I would not pour any more poison on it. Just focus on the tree, look into the reason for ill health. If you solve that the mould will go away.

the big balls, know fertilizer, if so, the mold comes from the

The bark on the nebari is totally stripped off on the upper side of the roots. Its possible that the mould comes from the fertilizer. I assume that the lost bark has been removed because it was dead and mouldy?

Mould on fertilizer is no problem, just natural break down that helps making the nutrients awailable to the tree. Mould on roots suggests an unhealthy tree. Healthy trees dont get mould on roots.

But also.....we always say dont fertilize an unhealthy tree. It does not make anything better. But please post a picture of the whole tree and tell us your conditions and care.

Thnaks a lot!

And nebari too...