Bulk Grain Storage - Plywood?

So I have a very limited amount of space in a closet below my basement steps to store grains, and I'd like to make something custom out of wood store sacks of grain.

Any concerns with using wood to make a box to store grains in? Any type of commonly available sheet goods wood work (plywood, mdf, fiberboard, etc) would work, but ideally I'd go with plywood, or melamine covered boards. Any concerns with this idea?

I haven't been able to find anything to fit the dimensions of the area I'd like to store them in, so that's why I want to go the custom route. Currently I have 3 sacks in a giant rubbermaid container that I have to drag in and out (100-150lbs!) to get to my fermenters... and needless to say it's getting a little old.

i don't see why wood wouldn't work for this application. if you're paranoid about it, line it with some sheet plastic or something... but again, i don't see what harm the plywood would do. is there any danger of mice or anything? you may be able to just stick the sacks under your basement steps without any modifying.

No danger of mice, thankfully. I know plywood is fairly stable in terms of moisture, but I wasn't sure the grains, or the wood, would start to extract moisture from each other. That was my biggest concern I guess, should have mentioned that.

Unfortunately the rest of the steps have been claimed by other storage, so there's no room. I have roughly 6" D x 48" H x 45" W space that I'd like to build a few tall/narrow boxes to store some base grains.

The Vittles Vault II 40# unit is tall & skinny and holds a whole bag of grain.