Manure Management
Jim Van Der Pol Our thinking about manure management springs from our study of the principles of Alan Savory's Holistic Resource Management. HRM got us to consider that manure is part of nature's cycle and as such it is as necessary to the health of the land as any other part of that cycle. Knowing that it is not possible to have production from land without return to the land, we came to believe that our role as farmers must be to facilitate that return with the least possible interference. What follows here is a description of the everyday work of putting these principles into practice. We decided that all crops on our farm would be consumed by the farm's livestock. This involves changes in the cropping pattern. We dropped soybeans from the cropping rotation, added hay, and built up livestock numbers. We built fence and expanded our permanent pastures to nearly 25% of our land base. We found that we could do a very good job with farrow-finish hogs on pasture seasonally. We expanded our grazing bunch to about 150 ewes and their young as well as several dozen head of stock calves. Pastures are rotated annually between these and the hogs, now at about 1200 head per year, to aid in parasite control. Animals are moved, or rotated across these permanent pastures every few days or weeks, depending upon what they are. (Hogs or sheep/calves) We find that it is most profitable and environmentally responsible to handle the animal so that it can find its food right at its feet (graze). This method involves the smallest use of purchased capital inputs and the stingiest petroleum use. The only energy use in pasturing is the electricity to run the fence charger. A grazing animal deposits its manure where it belongs, i. e. in the field it is grazing. This again is very economical in terms of energy and capital use. What needs to be added here is that the pasture being grazed must be managed for maximum growth and soil life so that the feces and urine being deposited are incorporated into the soil by the soil life immediately. Well-managed pastures are environmentally friendly, dirt lots are not necessarily so. The calves are sold at the end of the grazing season but the ewes are overwintered. Care is taken to keep them in the pasture and rotating (very slowly) during the winter feeding season. We want them out there so that their manure and hay waste will return to the soil, rather than being piled on the yard, incurring a fuel bill to haul it back out in the spring. Again, it is important that they be maintained on a well-managed sod so that as little as possible of their winter waste finds its way into the drainage during the spring melt. A well-developed sod with about a six inch residual going into winter does quite well we think. The hogs are seasonal. Even so, winter finds us with about 350 grow finish pigs and 50 sows plus 100 breeding gilts and boars to maintain on the yard. We have not yet found a profitable and workable system for maintaining the hogs in pasture in the winter. What we have settled on is the use of deep straw bedding in both our hoop barns plus the conventional barn and pole shed we use for livestock. The hoop barns are used for finishing hogs in the summer as well as winter. Additionally, sows are farrowed in them in early spring each year, by means of the pasture shelters placed inside. The barn and pole barn are used for gestating sow and gilt housing in winter. Breeding is done in the pole barn. The deep straw system for handling hog manure was an idea we picked up from visiting Swedish farmers in 1996. Some of the Swedes have built an entire system for hog production around the idea of using deep straw. We benefit from their experience in other ways on our farm, particularly from their well-developed understanding of swine behavior. The deep straw practice works well for us in our older and very simple buildings. The presence of all that material allows the hogs to manage their own environment to a certain extent while the straw ties up the nitrogen in the hog manure and holds it until it gets back to the field to be spread as fertilizer. This system does not produce that septic odor so common with other systems of hog manure management in use. We have found that the only odor produced is at cleaning time and that only last for a day or so. Other than that, our farm smells like livestock, not sewer. Straw (and cornstalk) use is about 25 large round bales for the breeding herd in the winter plus 400 small square bales for farrowing in the hoops and in the pasture. The finishing hogs in the two hoops will use about 140 large round bales yearly. The custom charge for baling this material is $7/bale for straw and $8/bale for stalks. Small squares cost $.25/bale. Straw baling cost comes to just over 1 dollar/head sold annually. It should be noted that the farm produces and uses hay both to feed ewes in winter and as a large part of the sows' winter ration. Therefore, we are equipped with bale racks, elevators, storage and moving equipment. None of these things are single use for us. In fact, handling manure as a solid as we do generally involves less specialized equipment than other methods and is therefore a safer investment. We bought a good front-end loader with bale spike as well as material bucket and fork attachment to install on our "haymaking" tractor for servicing the hoops. In addition to our manure spreader, we rent a large one from a fertilizer company to speed the spreading process. We like other folks to own the equipment and try to keep our equipment as multi-purpose as possible. Getting the straw and spreading the manures imply some adjustments in the cropping system. As noted above, small grains (barley, oats) have replaced soybeans in the rotation. We can feed the grain and we need the straw. The grains are short season, which also opens a window for manure spreading. This is definitely a consideration for a northern farm. Our major cleaning times are spring and fall. The sow housing is cleaned periodically through the winter, and the manure piled. The hoop barns are cleaned just prior to March farrowing and again in October before stocking with fall pasture farrowed pigs. To the present time, we have allowed the spring cleaning to remain piled on the yard until fall and hauled the manure all at that time. This has not been an environmental hazard in our view because of all the straw and because the piling site is surrounded by grass. However, it does entail some weed and rodent control and we are trying to change the practice. We are including some hay in the rotation for feed and because the nitrogen fixed by the alfalfa can replace some off farm expense. The alfalfa will be rotated in two years for these reasons so that half the acreage will be tilled each year and planted to annual crops and a similar number of acres reseeded. Attempts will be made to spread manure in the fall on the corn stalks that are to be planted to small grain and in the spring on the old alfalfa stand just before it is tilled and put to corn. This gets the manure application followed by a feed grain crop (oats, barley, corn) and should result in a steady state soil fertility situation over time, provided that we do not grow the hog operation to the point that we buy too much corn, thus increasing manure amount beyond the soil's ability to handle it. That is not a problem yet. It remains to be seen if we can till alfalfa ground in the spring and get it into shape for corn planting. Our soils are heavy and poorly drained and the farm is low. Spring tillage has never worked well. Our hope is that the root structure of alfalfa will allow us to get away with it. If it doesn't work we will need to dream up something else. Manure management is something that goes with all the other aspects of farm management. As an example our management discussions this winter will center around the advisability of building a good perimeter fence around the whole farm. This discussion has three parts. First, can we afford the capital investment and investment of time? Second, what aspects of livestock feeding will the fence improve? (Alfalfa grazing in summer by lambs and calves, gilt development by foraging in the fall, ewe maintenance on stalks all winter) Third, what benefits does it hold for manure management? The best manure management minimizes movement. It has the animal dropping the manure where it is needed and the soil ready to receive and reuse it. In the case of animals that must be housed in barns, our rule is: the simpler the better. Straw and stalks are cheap and plentiful. Their use allows barns to be simpler. Equipment is now available to handle straw and straw manure effectively. Care needs to be taken that the soil is ready for the manure. Diversified farms with their possibility of intense on site management are best suited to accomplish this. Concerns have been raised about the variability of solid hog manure as a fertilizer. While we think we can adjust for some of that by the way in which we clean the hoops and load the spreaders, it would be a good idea for us to start a regular program of manure testing and nutrient management.
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