By: Malcolm Beck
While growing up on the farm, my brother and I had to always keep the manure, soiled hay and other waste cleaned up from the chicken, pig and cow pens. It went straight to the fields or garden unless the soil was too wet, or there was a crop growing or planting was to be done in less than six weeks. If those conditions prevented going to fields we would keep the manure piled up high in a convenient location. In the fields, we would spread it thin, then Dad would disc it into the top 1 to 2 inches of soil. It was the only fertilizer our farm ever received. Nature accepted this raw natural soil food with open arms and rewarded us with good harvests. There was never evidence of soil fertility decline or wind or rain erosion.
If raw manure worked so well why do people compost if Nature can do it and has been doing it right on the soil? There are reasons. You would not spread pig manure on a city lawn or in a back yard garden across the fence from someone's patio or pool.
Composting greatly improves the look of manure, removes the odor, makes it more fun to work with and can destroy diseases, weed seeds and bad insects. Compost doesn't need to look and smell like garden soil before using it, unless you are going to plant seeds directly into it or use it around young tender plants.
In my fifty plus years of using manure and over forty years of making compost I have learned that large static piles (around 30 to 1 carbon to nitrogen ratio, aged six months or more, turned three or four times to make sure the blend is better and the outer sides get to spend time in the center) is the most efficient way to make compost. Turning compost too much can waste valuable nutrients into the air. With static piles, there is less energy input, and less moisture, heat and nutrient loss. This works for a small home garden or the large commercial operation equally well.
Large piles are preferable, because they contain the heat longer. This results in better pasteurization and the microbes have more time to degrade toxins that could come with the raw materials.
If you want to use compost from large piles, however, it may still be hot and have an ammonia smell. When spread on gardens, around plants, trees or on lawns, the heat and ammonia quickly dissipate into the air. The heat we no longer need, but the ammonia is a good form of nitrogen and should not be wasted. If quickly watered into the soil it turns to ammonium, a cation that is held in the humus and clay particles of the soil for future plant use. If not diluted in water and washed into the soil it can turn tender plants yellow or have some other minor but temporary effect.
Carbon dioxide is also trapped in large static compost piles, but when used shallow in the soil or as a mulch under growing plants, it makes plants grow faster. The carbon dioxide concentrations enable the open pores on the plant leaves to take in carbon dioxide quicker and stay shut longer. This helps the plants conserve moisture and allows plants to draw less moisture from the soil resulting in water conservation. Again, too many turns of a compost pile will waste this nutrient to the air causing pollution and possible global warming.
On my vegetable farm I got best results if I used the compost as soon as the microbial activity and/or heat destroyed the weed seeds and possible diseases. After spreading I would quickly blend it into the top soil and let Nature finish the decay while saving the moisture, ammonia and carbon dioxide.
I don't recommend that city folks or home gardeners use compost that still has a putrid smell. If the pile is still warm and has an ammonia smell and you are not sure, do the one hand smell test. With one hand dig into the pile, feel around and squeeze some of the material then go wash that hand. If a rank smell is left on that hand after washing or if it smells a lot different from the opposite hand the compost needs more time. Turning can speed it up.