Powder tends to be hydrophobic, so when added to a liquid it tries to grab the nearest non-wet thing (I find often it will attach to the glass around the edge of the jar). What % alcohol did you use? (not sure if powder also resists saturation by ethanol).
Is all the powder clumped or just bits of it? I would probably stirr it with a fork a few times a day to break it up and speed up the rate at which the extraction is happening.
I'm using 60% alcohol. It has all clumped up and I plan to leave it for six weeks before beginning my decoct extraction. I've been shaking it daily, but it doesn't seem to matter much since the bottom half of the jar it's solid matter.