Browse Forums Renovation + Home Improvement the leaves that are now underground go yellow, the tips that poke through photosynthesise and have chlorophyll, same reason they grow rhubarb in the dark. 5 4886 What you are looking at is fibrous plaster, true gypsum, it is cast on horizontal beds with fibers included to give strength. I has no Asbestos in it. Houses before 1985… 2 7140 4 1843 |