NEWARK, Delaware – A fifteen-minute walk from University of Delaware’s main campus transports students from the crowded sidewalks overflowing with construction to an oasis of peace, quietude, and UDairy ice cream on the university’s 350-acre outdoor classroom—the farm. This agricultural and environmental sanctuary just across the bridge on South College Avenue delivers an initially shocking aroma. On a working farm, there are large volumes of animals producing—as they do—large volumes of manure. However, this manure is good for more than just keeping the crowds at bay. With the right equipment and space, it becomes the fertilizer that keeps the farm functioning.
“It’s all part of the cycle,” explains Webb Farm manager Larry Armstrong. “What they make in the farm goes in the field [where] they graze.” Fifty Dorset sheep, thirty Angus beef cattle, and six teaching horses live on Webb Farm, all of which are managed by Mr. Armstrong. However, in his position, he serves as the caretaker for more than just the animals themselves as he also maintains the health of the land they rely on.
As someone who has been in agriculture his whole life, Mr. Armstrong sees value in products that others would initially dismiss as waste and waste alone. Whether it’s the piles of leaves that have fallen on the farm, the excess straw spilling out of horse stalls, or the physical waste piling up as the livestock convert food into energy—all of it gets raked, swept, and scraped up into skinny piles called windrows for composting.
There are two windrows on Webb Farm, piled up neatly between the horse barn and the sheep barn.This location is ideal for the windrows as they face the south side of the farm, soaking in the perfect amount of sunlight. With the right combination of sunlight and aeration, the piles “slowly decompose and shrink,” usually resulting in a “50% reduction or more on the volume of [waste],” Mr. Armstrong says.
The sunlight raises the temperature of the waste pile to around 134 degrees Fahrenheit (55 degrees Celsius), the optimal temperature for killing pathogens. The reduced waste products are ultimately used as a natural fertilizer across the pastures where animals graze, and any pathogens in the material would threaten the health of the livestock.
For over ten years, Mr. Armstrong has been compiling all of Webb Farm’s waste into windrows, turning them over when necessary, and spreading the resulting product on his soil.
The longer a material is composted before being used as fertilizer, the more “environmentally friendly” it becomes. “Raw manure is good, but [it is] more likely to runoff,” advises Mr. Armstrong. In the composted product, the cation exchange within the soil allows for stronger binding of phosphorus, thereby decreasing nutrient runoff and the corresponding ecological footprint of the farm.
Although the nutrient load within the composted material is decreased, it still adds value to the soil in the form of organic matter. Another important measure of soil health is its microbe activity—with the addition of this natural fertilizer, the “soil becomes more alive.” And with appropriate soil testing, Mr. Armstrong determines which of his fields needs the biggest boost in soil health when deciding where to lay the composted waste. With this specialized product, Webb farm relies on the use of zero synthetic fertilizers.
While composting itself may be a common practice, Larry Armstrong is a pioneer for this specific type of composting when applied to livestock. He got the idea after an informative visit to Longwood Gardens, a botanical garden with over one thousand acres of gardens, woodlands, and meadows in Kennett Square, Pennsylvania. There he found that the Gardens collect waste generated by the gardens themselves, the on-site restaurant, and the guests arriving is swarms each year. Since the early 1990s the Gardens have been composting, and their comprehensive facility now expands over five acres. With this space, they process 8,000 cubic yards of organic waste each year. The resulting product is converted to mulch and compost to be spread throughout the Gardens, promoting healthier soil.
Despite the upsides of composting, there are a few limitations when it comes to large-scale composting, including space, equipment, and cost. At the Gardens, the windrows are a whopping six feet by ten feet, thus requiring specific equipment capable of turning them over for aeration. This can be a costly undertaking, especially for a location not bringing in the annual revenue that the Gardens see. However, the return is rewarding in more than just healthy soil and mulch—the Gardens estimate a savings of $50,000-$200,000 in landfill expenses annually.
When asked what is next for the University of Delaware farm, Mr. Armstrong admits that he “would love to scale it to the dairy,” but sadly there is not enough space. Additionally, it can be hard to justify the cost of this additional management step.
However, the initiative spearheaded at Webb Farm is just the beginning. Other aspects of the UD Farm are going green as well, including the organic garden, UD Fresh to You, where produce is sold to onsite and to local restaurants.
When it comes to sustainable agricultural practices, education is key in balancing environmental health and the need to feed the world. In addition to serving as the Webb Farm manager, Larry Armstrong is a great teacher. From freshman year onward, students studying animal science are planted on the farm where they learn from Mr. Armstrong himself about the importance of the work he does. Honors students in particular have extra opportunities to spend time on the farm, raising dairy calves as freshmen and learning firsthand how agriculture is entwined with animal science and our everyday lives.
Though he has grown up with agriculture, he does not take any of it for granted and recognizes the value in sharing why he does what he does with each new class of students. His enthusiasm and passion for the livestock and the land he works with is contagious, drawing anyone and everyone into the world of agriculture, in which composting is a key component to sustainable success.