Sizu Riatto
Flush Hour · Chapter 8

Harvest Day

Score your harvest the way growers do: grams of mushrooms per gram of dry straw. Call it before you pick, weigh it after, and see how far you are from the Hundred Club.

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Opens on the book's tub. Change any number to your own and press Calculate.

The tub

Call the flush, then weigh it

Several tubs (optional)

Enter the dry straw and the flush you weighed, then press Calculate.

The formula

  • BE = fresh mushrooms ÷ DRY substrate × 100. Dry, because the water in the straw varies and the dry matter is the food
  • Your call in grams = BE you expect × dry straw (g) ÷ 100
  • The gap = |weighed − call| ÷ weighed: within 5% scores 3 points, 10% 2, 20% 1
  • Yield on the wet straw = mushrooms ÷ wet straw × 100: a smaller number for the same harvest
  • Bronze at 50% BE over the tub's flushes, Silver at 75%, Gold at 100%: the Hundred Club, a gram of mushrooms for every gram of dry straw
The book's worked example, Chapter 8. The book called 50% BE on 1,800 g of dry straw: 900 g. The first flush weighed 945 g (2.08 lb): BE 52.5%, a gap of 4.76%, 3 points. On the wet straw it is 15.75%. 52.5% is Bronze so far; Silver needs 1,350 g in all, 405 g more.
Check it. Write your first-flush call in grams before you cut a single cluster, then weigh the whole flush: it is Check It in Chapter 11.

Honest limits. Published BE for oysters on pasteurized straw runs from about 50% to over 100%, each from one trial with its own straw, strain and room: your tub is its own trial. A medal is a record of one tub, not a promise. The book's tub, its straw and its harvests were worked out on paper from published figures, not grown by us: weigh your own. Prices are illustrative, as seen in November 2026 (US mid prices, with UK beside where they differ), shown without a currency sign; put in your own. No yield or profit is promised. Everything stays in your browser: no sign-up, nothing stored.