thom@ewj01.UUCP (Thom Leonard) (09/27/85)
Carnivore vs. herbivore vs. omnivore: not so black and white as we would like to think. Pigs may indeed be omnivores, but the amount of flesh a hog is fed is pretty near insignificant, especially in China, where one group member cited use of omnivore (pig) manure. And the use of human manure as fertilizer in the orient can hardly be considered the use of carnivore feces, as only a small portion of the human diet is from animal sources. But this is not to say that there is something that absolutely prohibits the use of the manure of flesh eating creatures. Agricultural animals are primarily herbivores for various reasons, not the least of which is efficient conversion of sunlight into food for people. Where land is scarce, people eat primarily plants, with a little more elbow room, dairy products and flesh of herbivores may be included. I know of no agricultural society that raises more than insigificant amounts of secondary consumers for strictly utilitarian purposes. So we've little experience with carnivore manure. Since nothing that hints at being the last word on pet feces in the compost pile came up through the newsgroup, I decided to look a little further. Jeff Gage is a member of the Composting Consultancy of Seattle Tilth (Tilth is the organization for sustainable agriculture in the Pacific Northwest). The Consultancy has a contract with the city of Seattle to develop a city-wide "Master Composter" program to train individuals in Seattle neighborhoods in the art of composting, with the eventual goal of composting *all* yard waste in the city. As an adjunct to this program the Consultancy is also investigating the question of disposal/use of pet feces. Jeff is also working with the Seattle Zoo, composting manure and bedding. Seemed like he might have some clues for the kitty poop dilemna. At the Zoo Jeff and associates only compost manure from the herbivores. Carnivore feces presents several problems, not insurmountable, but not yet solved. The first of these is that various parasites and pathogens may be transferred to human hosts. Because of the high amount of nitrogen (proteins are nitrogen compounds) in flesh, animals that eat primarily meat naturally have more nitrogen in their feces. With nitrogen the agricultural fertilizer in most demand that in itself is not a problem. What is a problem is the compact, relatively dry form. Mixed with straw or sawdust, the scats don't really compost, they just dry out. This holds true for household carnivores as well. Jeff suspects that the way to deal with this problem is to make a sludge and combine this with dry, carbon-rich material for composting. While the Consultancy has only begun looking at the pet waste problem, Jeff does offer some general guidelines. If pet waste is composted, two things have to be kept in mind. The end use of the compost should be for ornamentals, not food crops. The compost pile itself should generate high temperatures to assure that most pathogens are "cooked" out of the raw material. Handling of the uncomposted material should be kept to a minimum. If the feces are mixed with the proper proportion of carbonaceous material and thoroughly composted, there will be no problem with excess nitrogen burning plants. In a few months, the Consultancy should have more to report on pet waste. At that time -- say in the spring -- contact Jeff Gage, Copmposting Consultancy for Seattle Tilth, 4649 Sunnyside Ave. N, Seattle, WA 98103. Thom Leonard, East West Journal, Brookline, MA, USA