A few years after seeing one of our systems at Sonoma Valley Worm Farm, Sandy L. constructed his O2Compost Micro-Bin. In operation since 2006, Sandy composts straw, dried leaves, dried grass clippings, and horse manure collected from local horse stables. He feeds the finished compost to his red worms, spreads it on the orchards at the ranch he manages, and uses it to make compost tea.