By Jacki Martinez Perkins
As farmers we all acknowledge the benefits and challenges of manure application and storage. Poorly handled manure can create challenges to food safety and water quality in the form of unwanted bacteria and pathogens, and increased fly populations. However, well-managed manure and pasture systems that maximize our natural ecosystems can greatly benefit the land, animal health and farm fertility.
Knowing the volume and consistency of manure that needs to be dealt with is key in determining what kind of equipment and handling facilities are best suited for the job. Location of these systems is also important since managers need easy access in all weather conditions. Beyond the basic structure of the storage facilities, drainage and driveways need to be constructed mindfully to mitigate wet areas and allow for enough space to maneuver any equipment.
When space and stocking densities allow, composting manure can be an effective way to mitigate fly populations and potential harmful pathogens. Properly composted manure may be applied directly to fruit and vegetable crops with little danger to humans. For organic certification and food safety, it is important to remember the 90/120-day rule which states that raw manure must be incorporated into the soil 90 days before harvest of crops which are not in direct contact with the soil, and 120 days for crops that do come in contact with the soil.
With regards to manure management, it is important to consider the presence of maggots. Insects, both beneficial and harmful, breed and lay their eggs in decaying plant matter and feces, which can pose an insurmountable challenge in identifying friend from foe.
When it comes to pasture systems, further consideration for the development time of internal parasites needs to be taken. Livestock should be moved to a clean foraging location, no less than weekly, to avoid high infection rates.
Pasturing livestock to manage their manure can be one of the best practices to enhance local populations of dung beetles. There are three types of scarab beetle known as the dung beetle. Rollers are what most people think of when considering dung beetles, as they are seen often in nature documentaries carting off elephant feces. These pooper scoopers form balls of manure and roll them away to a nest, where the males are able to guard this source of feed for their young. They are often equipped with a “horn” and powerful front legs to aid in these tasks. Dwellers are found living and breeding directly in manure piles. Tunnelers don’t live directly inside piles of manure, but transfer these nutrients to their underground tunnels. All adult dung beetles are equipped with a keen sense of smell and the ability to fly, allowing them to find choice piles of manure to feed their young. It is not the adult beetles that feed on manure, but rather the larvae. Adults subsist on primarily a liquid diet. This would lead us to believe that in dry years it may benefit the dung beetle population to wait the maximum time of four days before dragging pastures to expose manure patties to sunshine, thereby allowing adults proper nutrition.
In summary some best practices for manure management are as follows:
- Time management often plays a leading role. We must decide how to align best practices into our routine schedules.
- Adjust paddock size and/or stocking density to move animals on and off grazing ground as quickly as possible. Grazing livestock should not be left on a parcel for longer than three days to avoid back grazing, or grazing too short, which causes animals to eat too close to the soil surface and increases the likelihood of parasite infestation.
- Never return animals to a previously grazed area before 14 days in an effort to break the parasite cycle. Rest periods of 30 days, or longer, for each paddock are ideal, mainly for the health of grasses.
- Evaluate manure storage facilities for capacity and ease of use.
- Take a minute to assess insect populations and the health of the ecosystem as a whole.
Now, while our animals have been pulled in from pasture, is the time to study our options and make plans to manage our pastures, and the health of our animals by managing their manure.