About a month ago I ordered a young Acer Palmatum ‘Koto Hime’ and a similarly young Acer Buergerianum (trident maple) from eastern Canada. Both were probably started from cuttings one year earlier and still had very small root systems. When the plants arrived, what few leaves they had were dead. Presumably they started leafing out before shipping, but nine days in a box during this sensitive time for the delicate plants was too much for them to handle. I removed the dead leaves, placed the plants (err… “sticks”) in a greenhouse, and I have been dutifully caring for them, hoping for new buds to emerge. I try to resist being to fiddly with the plants. So far, no buds. I admit, these plants are probably beyond hope, but I am so keen to have a ‘Koto Hime’ and a trident maple for bonsai that I have decided to be even more proactive.
In an effort to keep the roots and part of the stems alive, I have grafted healthy foliage from an Acer Palmatum ‘Lutencens’ onto each. This is a longshot for two reasons. First, as I sliced the rootstock plants for the grafts there was not much green to be seen. It may be that the cambium layers are already dead (but perhaps not quite!). Second, I am in no way an expert in grafting.

For the graft: I cut an angled slice into each rootstock plant, and I cut a matching wedge-shape on each scion (sorry, no photo). I attached the scions to the rootstocks firmly with elastic bands, cut, wrapped, and tied with a simple slip knot. I dabbed some orange cut paste and thought some hopeful thoughts.
If the grafting attempts are successful, my hope is that the grafted leaves will sustain the plant so that the rootstocks will eventually put out some of their own buds and leaves below the graft. If that happens, I will eventually remove everything above the graft, leaving a plant which is 100% the rootstock variety. Even if these attempts aren’t successful, I think the idea of grafting to save the rootstock may still be sound. In hindsight, I would probably have improved my chances if I had tried the grafting a few weeks earlier when the cambium was healthier, but then again, at that time it wasn’t clear that drastic measures were needed. My grafting technique probably also needs improvement.
It is interesting to note that grafting as a means of propagation is often undesirable in the bonsai realm because grafting can leave unsightly scars. Grafting isn’t completely outside the purview of bonsai practitioners though. For example, it can be used as a means of adding more desirable foliage to established trunks. In this case, I am using grafting for a different purpose entirely: to temporarily sustain the rootstock on a leafless plant until its own foliage can take over.

An update on this: my attempt to save the rootstocks failed, although I still think the idea has promise. If I ever try this again I will keep the plant in the shade, in some kind of clear container that allows a bit of airflow but which retains humidify, and I will mist a few times per day. to keep the leaves moist.