The Chesapeake Bay watershed spans over 64,000 square miles and is home to 87,000 farms, many of which produce livestock.
The byproduct of this livestock production is manure, both a potential pollutant (if not carefully managed) and a resource to fertilize crops. Without pollution controls, nutrients not used by crops may volatilize into the air, leach into ground water, or run off during rainfalls. The latter leads to the pollution of rivers and streams, which ultimately deposits the polluted water into the Chesapeake Bay. Excessive amounts of both nitrogen and phosphorus feed algae, whose growth and decomposition impair the health of the bay.
Inputs of phosphorous and nitrogen to Eastern Shore streams are among the highest in the bay watershed. Graphic sourced from a USGS report on nutrient loads in the Chesapeake Bay Watershed (download here).
As public consumption of meat products has increased, the number of livestock in the Chesapeake Bay watershed has increased and become more concentrated. Large amounts of feed, along with the nitrogen and phosphorus they contain, are imported from the Midwestern United States. This creates an imbalance between the amount of nutrients coming into the region and the amount departing as animal products, leaving the Chesapeake Bay watershed with a concentration of excess manure nutrients.
Intensive grazing can have numerous environmental benefits
Improving linkages between local feed sources and livestock production would correct this imbalance. The technique known as “intensive grazing” can be a means to “rebalancing the scale.” Intensive grazing mimics natural patterns of bison movement, allowing pastures to rest and regenerate between uses. This has helped many farms meet most or all of the livestock feed requirements, resulting in a better on-farm nutrient balance. CBF recommends this and other practices that help farmers keep nutrients and sediment on the farm, rather than contributing to runoff that pollutes local waters. Meanwhile, the farm’s profitability is maintained or improved.
To succeed with intensive grazing, the farm must manage the intensity, frequency, duration, timing, and number of grazing animals on pasture land. This is done according to the rate of plant growth, density of vegetation, types of plants, and nutritional needs of the grazing animals. Warm season grasses may be needed for the farm to survive the heat and dry spells of the summer. Also, stored hay or silage is usually needed for the winter.
Cattle can be rotated through grazing areas to allow the grass to recover. Photo credit: Kelly O’Neill/CBF.
Healthy pastures have many environmental benefits that also support farmers. Improved soil health, less soil erosion, and less compaction preserves grazing lands, whereas more conventional grain-fed operations (or continuously grazed pastures) deplete the soil. A higher diversity of plant varieties and longer recovery periods allow for the development of deep root systems and increase water infiltration in heavy storms.
This protects local waterways by reducing soil erosion and runoff of manure nutrients and bacteria. Additionally, the increased capacity to store water safeguards the land from drought. The high organic matter of healthy soils helps to mitigate climate change by sequestering carbon in the soil. When cattle do their own harvesting, with reduced use of fertilizer and farm equipment, emissions of greenhouse gases (nitrous oxide and carbon dioxide) are reduced.
The bottom line in farmers’ pocketbooks
The bottom line is that improved grazing practices boost incomes and cut expenses. These operations generally have lower start-up and maintenance costs than confinement operations, with less need for specialized equipment, infrastructure, and manure storage facilities. Because cattle meet more of their nutritional needs from the pastures, costs of feed purchases are also significantly reduced, which (in most cases) more than compensates for the slight drop in milk or meat production. Veterinary expenses and the cull rates also decline: just by the virtue of the cows being outside and having space to physically move, cases of foot ailments, parasites, mastitis, and other herd health problems are reduced. Grazing operations also have lower fluctuations in income and costs, facing less risk due to the fluctuations of the economy and weather.
The Chesapeake Bay Foundation is working with farmers across Pennsylvania, Maryland, and Virginia. Photo credit: Kelly O’Neill/CBF.
There is a rise in consumer demand and appreciation for healthier meat and dairy products from grass-fed livestock. Consumers are connecting production methods with their own personal health, and also recognize their power to support environmental stewardship by paying a premium price for eco-friendly products. This provides a platform for the farmer access to additional marketing opportunities and allows them to sell their meat and dairy products at higher prices.
Improving grazing practices in the Chesapeake Bay
The Chesapeake Bay Foundation has partnered with organizations throughout Pennsylvania, Maryland, and Virginia to form the Mountains to Bay Grazing Alliance. This will expand outreach and technical assistance for grazers through field days, pasture walks, an annual state-specific planning calendar for grazers, a regional conference, and a quarterly grazing newsletter. Water quality, greenhouse gas, soil health, and economic impacts of intensive grazing will be quantified for eight farms, to share with other farms in the region who may be considering a shift.
We’d appreciate your suggestions: What do you believe are the most important factors for farmers to consider when deciding whether or not to adopt changes for improving the environmental impacts of their farms?
Read More
Successful graziers tell their stories
USDA 2015 report: “Grazing Economics: Conservation Solutions for your Pennsylvania Farm” (Download the report here)
Competitiveness of management-intensive grazing dairies in the mid-Atlantic region
Grazing Lands Conservation Initiative (USDA)
Kelly O’Neill is an Agricultural Policy Specialist with the Chesapeake Bay Foundation, a U.S.-based nonprofit dedicated to restoring the Chesapeake Bay watershed. O’Neill advocates for policies to protect water quality and to help farmers maintain soil and nutrients. Her passion for sustainable agricultural systems stems from her family, who has been farming in Pennsylvania for over 150 years. This connection inspired her to organize a dairy goat cooperative in Honduras during her service in the Peace Corps, and to advocate for environmental stewardship and family farms in Nebraska.
Ed Garrett
March 28, 2016 at 4:10pmCertainly improvements in grazing, especially correcting stocking rates and moving animals, can increase utilisation of growing forages. However, we cannot forget that nature still creates a mismatch between forage growth rates and nutritional content that cannot be met on a local or regional basis through changes in stock numbers.
Natural development of indigenous plants and animals demanded that plants either be perennial or slightly more aggressive in their growing habits than animals to produce year after year. Animals would move from old feed to newer feed as plants matured and became less palatable. Animals also gave birth slightly in advance of feed abundance to ensure best development of offspring.
As we have modified plant species and diversity, as well as seasonality of herds in hopes of a more uniform market structure, we became dependent on harvest and storage of fodder to fill in the valleys of pasture production between peaks, with rainfed systems experiencing multiple growth spurts. Periodic harvests spur regrowth of higher quality feed, so whether harvest is through grazing or mechanical removal of forage, multiple harvest points throughout the growing season push productivity upward.
The differences between mechanical harvest and grazing are mainly in redistribution of nutrients (animal manures left in fields during grazing) and changes in plant diversity, with both grazing and fodder harvests having unique impacts. Where we started to get things wrong, was when we attempted to solve labor issues through dependence on mechanical forage harvests and bunk feeding of livestock.
Temporary electric fences have made it more labor efficient to mob-graze pastures than in the past. But to maximise productivity, we must still maintain mechanical forage harvest. This both provides stock feed for slow growth and dormant periods of forages, and assists the grazier in maintaining a balanced plant diversity while improving palatability of pastures. The third piece to maintaining pasture quality though is the return of fed forages and manures to the field following proper composting.
Modification of grazing habits are simply one small step in optimisation of a larger cycle. While it is true that grazing animals drop fresh manure in areas where they graze, fresh manure differs in significant ways from stall and pen clean-out or slurry from retention ponds. When applied to a producing pasture, compost serves to nourish existing plants, feed soil biota, and moderate both moisture and temperature of the soil. Compost also provides a buffering medium to capture and slowly release high nitrogen urine and wet manure deposits.
Few, if any, regions provide the ability to fully support meat production without dependence on either manual intervention to store, process, and relocate resources, or accommodate herd migrations. Each advance in one area must be met with equal study and action in others to maintain system equilibrium.