"Humankind~despite its artistic pretensions, its sophistication, and its many accomplishments~owes its existence to six inches of topsoil and the fact that it rains." ~Unknown
Our county master gardener who teaches composting emailed me the link and doc below. The composting method at the link is simpler than the method she outlined below. We had a detailed phone conversation and here are my notes.
Efficient composting requires the right mix of nitrogen (greens), carbon (browns), oxygen and water
1 cu. yd. is the minimum compost pile size for holding heat well; there is no maximum size
Have a collecting bin or garbage can for incoming greens until you have enough
Start a new pile with 2 parts browns to 1 part greens by volume, mix it all at once
Add water as you mix the pile, moist by not dripping
Left undisturbed the pile should reach 120+ deg in 2 days; if not, add more greens
Left undisturbed the pile should reach 130-160 deg in 3-5 days
At 7-10 days or 100 deg, turn the pile. Repeat this 3-4 more times or when pile no long reheats.
Best to turn inside-out since the center is the hottest. Mix in water so only moist, not dripping
Let the compost age for 4-8 weeks; otherwise, it will draw nitrogen from the soil when applied
This full cycle is then 2 to 3 months
If you don't mix browns/greens all at once and don't let the pile sit, then it cools and takes longer
She's measured 140 deg piles even in winter
Longer, cooler wait periods are ok but 7-10 days or 100 deg are the most efficient to turn
Hot composting, as above, is more effort and needs more materials all at once
Cold composting is much easier but can take a year or more, plus leach nutrients, attract pests
The two main cold composting examples are leaf piles and straw+manure, both left to sit
A high peak temperature helps kill volunteer seed
Different aerobic bacterial take over at different temperatures; bacteria get air during pile turns
Worms will self manage and seek the cooler parts of the pile
Is not enough rain in Central Oregon so don't cover piles with tarps; it would also reduce air
Browns: sawdust is the highest nitrogen. Straw is good along with leaves. Newspapers are ok.
Suggests no dirt; it adds weight and is a low-quality brown
Greens: the variety of greens we have is very good; composting is more efficient if chopped smaller, 1" or less
Suggests bins with screen sides or screened-pallets for better air, not straw bails or solid walls
One oxygen vent pipe is enough for our current bin; more would cool the core too much