I wouldn't worry much about it at this time of the year, but here, I almost always shake all the soil from the roots/rhizomes first and then let them dry out for a few days in the sun before putting them in the compost pile.

Kt

If they grow roots, just pull them out of the compost and throw them in the garbage. They're not going to go crazy if they do ....

Thanks. I've heard so many horror stories of bamboo going wild, I don't want it to get out of control anywhere!

Maybe if you left the roots in the compost pile for about 5 years and ignored new bamboo culms shooting out of it you might have a problem, but most stories about bamboo going wild are either exaggerations or are from people who have not done anything to maintain their bamboo for years.

If you do get any root growth, you can pot it up and get new plants.