We need a language to read a book, and that affects our thought process, as we start thinking like the author and behave in a manner we perceive from the books. Like how someone speaks under the influence of alcohol, books n authors too influence.
Sawdust that is created from cutting natural wood is safe for your compost no matter what kind of tree the wood comes from. Just make sure the wood has not been treated with any chemicals. Another option with sawdust is to try mixing it in with potting soil.
Two types of material are generally used for mushroom compost, the most used and least expensive being wheat straw-bedded horse manure. Synthetic compost is usually made from hay and crushed corncobs, although the term often refers to any mushroom compost where the prime ingredient is not horse manure.