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All good advices. Two reasons I'm asking about composting the "right"
way is because A) I don't want it to start stinking by having too much
nitrogen and B) I want to minimize the time so I can start using it
this summer. Being an engineer I tend to overthink things. No, it's
not rocket science, but I'm sure some ratios are better than others so
I'm trying to learn from other's experiences from the start instead of
trial and error on my own.

Just so I have an idea, is that 50/50 brown/green by weight? Would
make sense since it's the amount of material that would be working
with each other. That 30:1 ratio is probably by volume because brown
is so much lighter. We probably generate a few pounds of green each
day. That's a lot of leaves I have to keep around to keep up with the
green since brown is so light...Perhaps once I get the pile going it
would regulate itself so I don't have to worry so much about what I'm
throwing in.


Any mixture will eventually rot into perfectly good compost given enough
time. If there is not enough nitrogen in the pile, it will just take longer
because the bacteria population will be limited by the amount of nitrogen
available.

It won't get stinky unless it goes anaerobic, so just make sure the pile can
breath well enough. There are lots of ways to do this: keeping the pile
smaller, adding materials with a lot of "structure" (like hedge or woody
shrub trimmings, stalks from last year's sunflowers, etc.), or turning the
pile frequently. Big piles of grass clippings or wet leaves tend to mat
together and reduce aeration. Mixing a whole bunch of different things
together helps avoid that.

During much of the year my pile gets essentially nothing but kitchen scraps
added to it, but during that part of the year the pile is small so it still
breaths and has never gotten stinky. During other parts of the year I have a
huge excess of "browns" (e.g. shrub trimmings, autumn leaves), which just
slows the decomposition down a bit, but everything works out in the end. The
only thing that would keep it from decomposing entirely was if the pile
dried out and stayed dry.

There are three different groups of decomposition bacteria that are
maximally active at different temperatures:

psychrophilic -- 32-50 degrees or something like that
mesophyllic -- 70-90 degrees
thermophilic -- ~140 degrees

I probably have the exact temps wrong but you get the idea. The theory that
if you don't have heat and steam, something is wrong, is IMO not true. It
just means you are not in the temperature zone of the thermophiles. If you
want really fast decomposition, yes then you need to get the thermophiles
busy, which means getting enough nitrogen in and a large enough pile so you
can have a bacteria population boom and retain the heat. (A book I read on
composting recommended animal manure for nitrogen.) The high temperature
also helps kill weed seeds and other pathogens. However, if you did not put
weedy, diseased inputs into the pile, this is not that important, and this
same book claimed that the finished compost that retains the most nutrients
is that which is mainly produced by a mesophyllic decomposition. If the pile
is small (~less than two cubic yards), it can't retain enough heat to get
the thermophiles going and you will get mesophyllic decomposition when the
weather is warm enough, and psychrophilic (very slow) when it is colder.
Another problem with thermophilic piles is the temperature kills many
desirable soil organisms, other decomposition bacteria, and those wonderful
decomposition workers known as red worms. Finally, if you have a
well-aerated pile that is large and well-insulated enough, it can actually
catch on fire from thermophiloc decomposition -- so if you are going for
hot, make sure the pile is in a safe place! (If you have a small pile and
really want to achieve thermophilic decomposition, the same book recommended
covering the entire pile with a six-inch layer of soil to help insulate it.
Good soil -- such as soil you have been adding finished compost to for
several years -- also contains significant nitrogen and a broad array of
decomposition organisms.)

The short of it, in my experience, is just throw whatever you have into the
pile and don't worry about it. Turn it once in a while if it needs aeration,
and water it once in a while if you have a dry spell. Nature will take care
of the rest for you.

Kevin