A leftover piece of material is commonly referred to as a scrap.
Leftover material can be referred to as scraps, remnants, or remnants.
A material scrap is typically referred to as a waste material, leftover material, or remnant.
Scrap
Waste
Leftover material is called scrap.
Residue or remnants.
extra, waste, scrap
extra, waste, scrap
It is thought that Asteroids are leftover material from unfinished planets.
One option for leftover butcher block material is to repurpose it for smaller projects such as cutting boards, coasters, or shelves. You could also consider donating it to a woodworking shop or using it as a decorative element in your home.
Yes it is organic material and can be put in the garden.