Manure: Nature's Recycling System - Jay Mertz
Manure is the oldest and most effective fertilizer known to man. As long as man has used domesticated animals and worked the soil, manure, which is sometimes referred to as "dung" has been used to feed the soil and plants. Manure can return 70 percent of the nitrogen, 75 percent of the phosphorus and 80 percent of the potash that was taken from the soil to feed the animals. This is not a bad return if you consider a dairy cow produces 27,000 pounds of manure per year.
For thousands of years this was the perfect system between man, animal and nature. Mother Nature, herself, invented this system. All we have to do is travel through the countryside and look at the forest to see this system in action. The plant life flourishes, taking nutrients and trace minerals from the soil. As the plant completes its life cycle, material is returned to the forest floor where it is mixed with animal waste, decomposes, is consumed by earthworms, and used to feed the next cycle of plant life.
The value of manure was still understood when man moved to the city. It was gathered, piled outside city gates where all could share in its value. Without manure to place in the field, the nutrients and trace minerals in the soil would soon be depleted and the land would no longer support a commercial crop. Part of what supported the westward movement in this country was the practice of early farmers using up the land and moving West to more fertile ground. It is sad that even today most farmers do not understand the proper use of manure and simply dump it on uncultivated land for disposal. Only about 1/4 to 1/3 of the true value of manure as a resource is realized in this country. In many highly populated countries a farmer cannot move. He has learned to feed the soil with manure, this is the only form of fertilizer available. Human waste, called "night soil," has also been used.
Agriculture in many nations could not succeed without the use of all types of manure. To better understand the use of manure you can read the works of F. H. King and Sir Albert Howard. King wrote Farmers of Forty Centuries. In his book he states that Asian farmers successfully fed their huge populations by returning everything to the soil. Sir Albert Howard wrote "An Agricultural Testament." This book was about composting and the use of manure and "night soil" in India. If you plan to visit Mickey Mouse at Disney World and The Epcot Center, you will be able to see "night soil" at work in the compost made and used at Disney. Old Mickey is pretty smart!
When motorized cultivation and the use of man-made fertilizers became common, the chain of harmony between man, animal, soil and plant was broken. Monoculture became the standard. When man raised animals, used the manure to feed the soil and plants we had a closed circle. You only have to look back at the turn of the century to see it work at its best. A local farm raised a cash crop of cotton, balanced with corn and peas to help feed and animals and the farm family. There were draft animals, hogs, chickens, cows, and a family garden plot to produce. The manure was spread on the soil as a fertilizer to replenish the nutrients and trace minerals which had been removed in the process of harvest.
Today in the monoculture system we depend on large applications of commercial fertilizers. There are no animals, only large tractors to do the work. Animals are being raised in this system on hog farms, chicken farms, cattle feed lots, large dairies, etc. for the most part this manure is placed on uncultivated land where it is wasted. We will soon be up to our eyeballs in manure if we don't close the circle and put this natural fertilizer back to work on cultivated fields.
Commercial composters realize the value of manure today, and are hauling it in by the truck load to compost. In the Texas hill country, turkey manure is being mixed with leaves and grass to make a very rich compost. In the Metroplex, horse manure and bedding material is being turned into compost. In San Antonio, manure, food waste, wood waste, and leaves and stems are being used for compost. Denton, Belton, Austin and Bryan/College Station are mixing "night soil" with leaves and stems for compost. Human waste is being cleaned, sterilized, and pelletized as a fertilizer. Several companies bag this material and sell it to retail nurseries and landscapers.
When looking for a manure source, consider the value of feed the animal has eaten is it rich in alfalfa, balanced with trace minerals, or was it a low protein hay? The point to remember is that any manure is better than no manure, but if we have a choice, choose manure from an animal that is well fed. Good sources of manure are riding stables or places that board horses. Check out the area where ranchers feed bales of hay to their cattle, as this hay is mixed with manure and generally goes to waste. This material is perfect for compost, or use as a mulch. Feed lots, auction barns, poultry farms, and rabbit raisers are all excellent sources for manure. I have probably left some out, so use your imagination.
When collecting manure you will need rubber gloves, a face mask, plastic garbage bags, rakes, and scoops or shovels. Aged horse manure is very dusty and you do not want to breathe this dust. It is amazing how much cow manure can be picked up in a field in an hour with a plastic bag and pitch fork. Have you ever sailed cow chips? It can even be fun.
All Not Equal
All manures are not equal. Seventy-five to 80 percent of all the nutrients an animal eats will be returned to the soil in the form of manure. Human waste is best, however, because of the human protein block. Next would be rabbit, then horse, sheep and goats, well-composted poultry manure, cow , and steer. The manure value can change depending on the quality of the feed ration. For instance, dairy cow manure will have a higher fertilizer value than the field cow. Rabbit feed contains a high level of alfalfa meal balanced with vitamins and trace minerals. It has just the right balance to make it the superior manure. Take into consideration the differences in the animals' diets.
How To Use
Okay, we have our manure, now how do we best use it? Some manure should be used in all compost piles. The nutrient values can be stretched by using it in the compost pile or vermi-composting in. Poultry eliminates their urine with their feces, therefore, limit poultry manure to not more than 20 percent by volume due to the high content of urea. Roses love rabbit manure, cow manure and alfalfa. Mix rabbit manure or cow manure, a little alfalfa meal, and lava sand into the soil when you transplant a rose bush. Next, top dress over the plant's root system with lava sand, rabbit manure or cow manure. With each watering you will feed the plant. Mix manure into the soil of any planting bed. Composted poultry manure is excellent for your lawn; spread the manure and water in. In the fall place a 6-inch layer of leaves or compost with a ¾ inch layer of manure on top of your produce garden. In January, till this mixture into the top 6 inches of soil. As the garden grows, top dress over the root zone of the plants with manure. As you water your garden you will feed both the soil and the plants. It is always best to partially compost manure before using.
Another excellent use of your manure is to brew up some manure tea. Manure tea is easily made and can be used as a liquid fertilizer. Age the manure for 30 days in water and dilute it to look like weak tea. What makes manure so valuable is that we are returning to the soil that which came from the soil. Manure is alive with good microbes, bacteria, enzymes, fungi, and trace minerals. This feeds the soil much more than the N-P-K of commercial fertilizers. You are returning organic matter which is converted to humus, which makes the nutrient elements available to the plants. Feed the soil and you will feed the world!
Jay Mertz is the owner and operator of Rabbit Hill Farm.
This article originally appeared in the May/June 1997 issue of Texas Gardener magazine.
Reprinted with permission of the author and Texas Gardener.