I have been very thrifty saving all my large batting scraps! BUT..... now that I want to use some I am No longer sure which is cotton, bamboo or poly/cotton mixture. I now label all my offcuts but when I was a newbie I didn't realise the need.
Does anyone have a method to help me discriminate between these? I feel they will wash and wear differently if I mistakenly join them and use them in scrap quilts. Thanks for any input! I am really cheesed off with myself as I am usually more organised.

Only advice I have is to try to match the scraps by color and thickness.

Just wanted to let you know you aren't alone as I had the same problem until I realized it would be wise to put the batting scraps into the bag the batting came it. Simple solution but it took me awhile to think of it. Good luck, May in Jersey

That is what I did, by matching color and thickness. I usually buy my batting at the same place so this was easy to do, but I plan to branch out on trying diffrent battings so maybe I should start marking it.

I only buy the same brand/type of batting so I don't have this quandry. I also only buy king size no matter how big I really need so I can have big pieces for small projects.

I bag mine and label...learned this early on....thank goodness

Maybe use the ones you're unsure of for wall hangings .. or .. snip small bits from the ones you think are the same, stitch together and wash to see the outcome -labeling as you go ... HTH :D