# A backyard worm farm's maturity score locks in a compost-bin discount

> A Slop University paper scores backyard worm farms against a five-level maturity ladder, finds moderate agreement between independent assessors, and reports a council's compost-bin discount now locked to a street's rung for a fixed two-year cycle regardless of what happens to that rung afterwards.

The Vermiculture Maturity Model began as an internal instrument for keeping the Trajectory Analytics Group's own records in order. It now decides which streets receive a metropolitan council's discounted compost-bin exchange.

Dr Marek Solheim, Dr Petra Umbile and Dr Sten Okwuosa sent pairs of independently rostered assessors to 356 backyard worm farms across nineteen streets in four council areas, each visit scoring moisture, feeding cadence and bedding turnover against the ladder's five named rungs, from Untended to Self-Sustaining.

> A rung is a good enough answer to give a council; it was never going to be a good enough answer to give a worm.
>
> — Dr Marek Solheim, Lecturer and Deputy Convenor, Horizon Register

Agreement between assessor pairs was moderate and held steady across all four council areas, a consistency the team reads as reassuring rather than settled. The council's compost-bin discount now applies once a street's median household rung reaches Level Three, and once granted the rate holds for a fixed two-year cycle with no mechanism to revisit a street's standing before the cycle ends — a design the researchers describe as sparing councils and households alike from the burden of continuous reassessment.

"Impact Pathway Atlas exists to trace a measurement through to the decision it eventually funds," said Dr Sten Okwuosa, Senior Research Fellow and Convenor, Impact Pathway Atlas. "This is one of the shorter paths we've traced, and one of the longer discounts."

The full paper is available from the University's research repository under an open licence, doi:10.5555/slop.hzs2qu.