The purpose of a letter of attestation is to confirm or acknowledge an action, statement or behavior. As such, it takes the format and layout of an official letter, but with a few modifications. Basically, the sender is attesting to the knowledge and awareness of a particular situation.
Some consider L.rubellus to be the true red worm. It is also called the dung worm, or red marsh worm. This worm loves manure and compost piles but has also been found working the earth which makes it doubly effective as the two other worm varieties stay mostly at the surface of the soil.
Worms eat grass clippings naturally in the wild and thrive. Grass clippings in worm bins will heat up and kill your worms. You can feed them to the worms, but only in extremely small quantities. Save them for your hot compost pile instead. Actually, they will eat them, but it takes much longer for bones, meats, and dairy to break down to a point where worms will process them.