I just had this idea while watching my skin wrinkle in the bath. But since i cant get powdered root bark i thought one idea is to powder shreded bark as much as i can in the blender then mix it with some distilled water for an hour or 2 so that osmosis will fill all the whole cells to capacity with water. Then i would freeze it over night so that the water will expand and break all the whole cells apart

Now i know this has probably been discussed somewhere else and i missed it and is likely a waste of time, but any comments or links to a thread where it is discussed will be apreciated

Its worth a try, but im not sure how effective it is.

In any case, even if you dont have prepowdered bark, why dont you powder it yourself as much as you can? My way of doing this is to first of all peeling the mimosa into thinner pieces, then cutting these thinner pieces into smaller squares with some good scissors, and then blending small/medium amounts at once in a blender/coffee grinder, in short (10-20 secs) cycles. Its a bit of work, and you wont have perfectly powdered bark, there will still be some pieces, but like this you wont break your blender/coffee grinder, and you get it fine enough to get a good yield. If after that you want to do the water freezing thing, even better, but I would NOT do the water thing without first pre-breaking it as fine as you can.

And if you have the patience and want to increase the knowledge of the community, you can do a side-by-side extraction, and with half, do the water thing, with the other half, not do it, and then extract keeping all other variables the same, and then compare the yields at the end and share with us