Is there a way to tell if fabric has dry rot before you sew with it or do you have to wash it in order to do this? I have used some old (i guess) black material from my mil's stash in a quilt and it just fell apart literally when I washed the quilt. Thank goodness not much time was spent on it and it was small. The material just ripped and even seem to disappear! I just tossed it away from frustration and didn't think to take a pic to show you. Has anyone had this problem before? She had washed it but it could have been 30 years old and I don't know how it was stored.