Five Year Native Tree Challenge: Esolin's Smokethorn (psorothamus spinosus)

Esolin

Shohin
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This desert plant has many regional names, the most common name around here is 'smoke tree' but apparently there's a European species called 'smoke tree' that came up when I did searches, so to avoid confusion, I'm calling it a smoke thorn, which honestly sounds cooler. It grows in sandy washes and sends a huge taproot down to anchor itself and draw water year round. They also look bare like this most of the year, leafing out only for a brief time in spring. But they photosynthesize through their young green stems even when bare.

This one is um ... small. Not even the width of a pencil. But that's what they sent me. *shrug* I hope it puts on some trunk girth fast. At least the limbs are still soft and reposition-able.

smoke1.jpg smoke2.jpg

Now the question is, when and how to work on it? I don't know what they like/hate as I couldn't find any on the web that have been bonsai-ed. It's getting ready to sprout flowers/leaves for the Spring. I assume that's what these orange nodes are:

smoke3.jpg

So I should probably wait to wire it until after it drops its leaves this summer, but should I work the roots while it's 'active', or wait until Fall/Winter after the heat of summer passes and it's getting ready to wake up again? Lots of questions with unknown answers. It's going to be a curious journey--assuming I don't kill within the year....
 

Esolin

Shohin
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I'm beginning to think I know why there are no bonsai of this species. More research has revealed that messing with the taproot even on young trees can be fatal. It seems they truly do not tolerate any root work, so long term success with keeping them in pots is probably impossible. But for five years? Maybe, if I'm careful.

So what did I do? I repotted it. :p There was rain in the forecast and I decided that my best chance for successful repotting would be during a cold rainy week, which is when desert plants become active. (And I decided that if even lightly touching the roots is gonna kill it, then I'd best get it over with!)

The primary roots were very tuber-like, which makes sense if they're used for storing water pulled up from deep beneath the desert sands. It also had nitrogen-fixing nodules packed around the root crown, so it definitely is in the legume family. I tried not to remove any roots (and there weren't many, honestly), but the fine feeders were extremely delicate, and just the weight of the soil falling way broke some off. There was also some evidence of root rot, possibly from too much moisture being held in by the loose organic mix it was in. I repotted it in 2 parts pumice, 1 part akadama, and 1 part of the organic stuff it came in.
smoke4.jpg

It's possible the 'new pot' is too shallow for this deep-rooting species, and I might double pot it to keep the roots cooler in the summer. I replaced the bamboo support rod with a loose-coiled wire to hold it against the wind. I hope it survives. I do love the way the branches curve in a natural sort of fractal pattern. It reminds me of deer antlers. I hope it survives. And I hope it blooms this year.
smoke5.jpg
 

Esolin

Shohin
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....And it's dead. Repotting must've killed it as it never leafed out and all the branches slowly turned brown. Not really surprised, but still disappointed. It would've looked cool in bloom. Alas, this is not a species suited for bonsai. Thankfully my other three contest entries are growing like crazy. I'll be focused on them from now on.
 
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