I understand that pine roots - at least of some species - will not grow in contact with galvanized drainage mesh. (I have seen no explanation of this, but have seen pictures that prove it.) So I would think that galvanized wire would not be good for tie-down purposes - who knows how many other species’ roots also react badly to galvanized steel?
I’m quite surprised, then, to learn that Ryan uses galvanized wire for his tie-downs! Can anyone shed any light on this?
I think it might be more the mesh itself upsetting the local balance of water-O2 than the galvanized mesh. In a blog post a couple weeks ago on Bonsai Tonight a repotting was shown where there were no roots around the drainage holes as well, but it was not galvanized mesh just the regular ‘bonsai’ mesh: https://bonsaitonight.com/2018/03/23/repotting-a-jeffrey-pine/
In any event, in a recent stream Ryan was asked about galvanized wire and roots, and said he’d never had trouble. I’m going to take his word for it, at least far enough to try out the galvanized.
I’m also going to watch for similar reactions from species outside the Pinaceae - whether their roots also tend not to grow well right over the mesh. (Or, in the case of a water -lover like bald cypress, grow like crazy!)
1: Keeping the drainage hole OPEN and free of roots is very important. Ive never got used to metal mesh. I use plastic(needlepoint ) mesh and COPPER wire staples. The galvanic [electrical charge] action of copper or galvanized metal [I ASSUME] irritated the roots and bugs. Keeps drainage OPEN. This is good. Copper and the zinc coating is slightly poisonus.
2: At a Ryan workshop we repotted a about a dozen ponderosas. All were tied with 17 ga galvanized horse hotwire and screws or chopstiks. Everyone one of them I have seen since then are crazy healthy. My 2 are absolutely amazing.
3: I use about 14ga steel wire. Works fine. Wont rust fast enought to matter.
4: the wire is fine. I think the quality of the type of wire is the reason. It doesent oxidixe at all… t’s tensile strength is the reason he uses it. Aluminum and copper stretches. Tree gets loose and moves. Kills roots.
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I always tie down with steel wire; always use copper wire on the drainage mesh.
I’ve done bonsai since about 1970. I’ve learned more into the last five than the rest. My trees are better because of Mirai.
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Balance of water and oxygen… hmmmm…ohm…