Gene Logsdon: Throwing Away Billions of Dollars In Pet Manure
Posted Aug 18 2010 9:18am
Not until I was well into writing my new book, Holy Shit: Managing Manure To Save Mankind , which is about how to manage manure for soil enrichment, did I realize that cats, dogs and horses are a very significant source of valuable fertilizer that we are mostly throwing away. Or, as our friends’ cat, Django, indicates in the photo above, flushing it down the toilet. Until I got to know Django, my attention was focused on farm animal manure and human manure. I was really surprised to find out how much feces, urine, and litter that pets were adding to our overflowing waste stream, let alone realize that cats were learning how to use the flush toilet.
Instead of wringing hands over the problems of livestock manure, the non-farm sector of society might first want to take a closer look at its own problem: manure from pet cats, dogs, and recreational horses animals that have little or nothing to do with putting food on anyone’s table. According to recent statistics, there are 73 million pet cats in the United States in addition to an equal number of feral cats roaming the alleys and fields (and killing millions of songbirds). There are some 68 million pet dogs and of course millions of strays out there doing beneficial work like killing my sheep. In addition there are some 9.5 million horses and the number is rising.
The numbers I use in Holy Shit to calculate the amount of manure flowing from these pets can only be approximations but they are based on the best statistics I could find. A horse weighing a thousand pounds produces about 20 tons of manure a year including bedding. So unless I can’t multiply any more, 20 X 9.5 million equals 190,000,000 tons of road apples. Pet dogs and cats together produce per year another five million tons of manure. All this waste is good, holy fertilizer. Dog and cat waste is particularly valuable because, compared to most manures, it is higher in phosphorus, the plant nutrient most difficult for organic farmers and gardeners to come by naturally.