At happy hour the other night the topic turned to human manure. We had all heard that human poop can’t be used as manure, or in compost, but we weren’t sure why. What about vegans? Can you use vegan poop in your garden?
ML did some research and uncovered this page about The Humanure Handbook.
The Introduction hits on a point, and some questions, I’ve wondered about for a long time -
“In the United States, humans take flush toilets for granted. You take your dump into a large bowl of drinking water, then flush it. End of story. That’s the civilized thing to do. But where does the flushed material go? What would happen if everyone in the world crapped in their drinking water supplies? Why doesn’t any other land mammal defecate deliberately in water? Why do we? These all seem like questions any reasonably curious person would ask once in a while.”
So, what’s the story? If it’s possible to use human crap for the crops, then why do we think it’s full of disease? Well, because it is. Full of pathogens, anyway. You can’t just apply shit to the soil, you must compost first. And if it’s composted properly, there’s nothing to worry about.
“Raw humanure carries with it a significant potential for danger in the form of disease pathogens. These diseases, such as intestinal parasites, hepatitis, cholera, and typhoid are destroyed by composting, either when the retention time is adequate in a low temperature compost pile (usually considered to be two years) or when the composting process generates internal, biological heat (which can kill pathogens in a matter of minutes). Raw applications of humanure to fields, on the other hand, are not hygienically safe and can assist in the spread of various diseases which may be endemic to areas of Asia. Americans who have traveled to Asia tell of the “horrible stench” of night soil that wafts through the air when it is applied to fields. For these reasons, it is imperative that humanure always be composted before agricultural applications. Proper thermophilic (heat-producing) composting destroys possible pathogens and results in a pleasant-smelling material. Low temperature composting, given adequate time, will yield a compost also suitable for agricultural purposes.”
Copies can be purchased here, or you can read it online here.
(Thanks, ML!)
The Humanure Handbook has been and remains to be such a service to humanity. Taking water out of the equation of ‘sewage’, transmuting pathogenic materials in to nutrient rich fertilizer, and debunking the whole concept of ‘waste’ by raising some really important questions. Go beyond the novelty of it, try it! That’s what I’m doing.
Cheers
actually, “any other land mammal” DOES “defecate deliberately in water.” i’ve seen dogs poop in the water at the dog beach more times than i can count. and it certainly seems deliberate! sometimes they’ll go INTO the water to poop, then run back OUT on the beach to play.
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