Applique pieces
My stepmother passed recently, so I was helping to clear out her personal belongings. She was a sometimes quilter, and I was given her 'stash. We found one mostly finished quilt, some notions, and literally hundreds of applique flowers and tulips of all sizes. Some of them have what appears to be dryer sheets to add stability(?). Some have a semi-stiff fused piece with the edges turned over, and stitched with large stitches. Some have been sewn onto a lightweight muslin, then turned right-side out.
On these pieces, there is a slit on the back. My question is: should I leave these as is, with the slit on the backside, or should I trim the backing piece away? If I leave the backing on, would that cause the fabric to weaken, or expand over the years, or would the eventual quilting secure the pieces?