An Apple a Day
How Green Is Our Valley
The National Zoo is the only zoo in the United States to grow all the hay it needs to feed and bed down its animal residents. The hay grows on the Smithsonian Conservation Biology Institute’s 3,200-acre facility next to Shenandoah National Park. This amounts to about 185 acres of hay fields yielding between 12,000 and 16,000 bales of hay. That’s more than 400 tons!
This hay goes to feed all the herbivores at the Zoo—everything from oryx to elephants to zebras—and also provides bedding for a number of other animals, including small mammals and great apes. Mike Maslanka, the head nutritionist at the Zoo, supervises this effort, which includes rotating fields, planting seeds, and harvesting the hay. Maslanka explains that the benefits of growing our own hay are tremendous.
“We can control the species composition [of the hay] for nutrient content,” Maslanka says. “We’d have a hard time buying the low-protein hay we want while still keeping it weed-free. We still scramble sometimes with weight management [of the animals] but it’d be a lot harder if we had to feed them high-protein hay.”
Growing our own hay also means that the Zoo animals have hay even in bad growing years afflicted with drought, cool spring or fall temperatures, or insect pests, when other farmers are short on it. Our nine hay barns can store about 600 tons of hay, which is about a year-and-a-half supply.
Protecting Native Species
In this area of the country, farmers typically grow what are called “cool-season grasses.” These grasses include the famous “bluegrass” (Poa pratensis), but also timothy (Phleum pretense), red fescue (Festuca rubra), Bermudagrass (Cynodon dactylon), and orchardgrass (Dactylis
glomerata). The grasses typically grow early in the spring when the weather is wetter and cooler, slow during the summer heat, and then reinvigorate in the fall if the weather is wet enough. Maslanka explains that cool-season grasses are usually easier to grow. Almost all of the hay growing at SCBI currently consists cool-season grasses.
A problem, however, is that most of these grasses are not native to this area and may not be the best choice from the viewpoint of the wildlife that lives on our land. Warm-season grasses are native alternatives to the typical cool-season grass fields. These grasses, which include big bluestem grass (Andropogon gerardii), little bluestem grass (Schizachyrium scoparium), indiangrass (Sorghastrum nutans), and switchgrass (Panicum virgatum), don’t look like the typical lawn. They grow in bunches and get very tall. They grow exceptionally well during the dry summer months when cool season grasses are either slow growing or dormant. Their height provides cover and habitat for wildlife when cool-season grasses are short and being harvested.
The warm-season grasses would allow the SCBI team to provide more appropriate natural habitat for native birds including bluebirds, bobwhite quail, turkey, bobolinks, and a variety of native sparrows. Maslanka explains, “From a wildlife conservation standpoint it helps us. In the spring our first cut [harvest] is usually around when the first clutch of bluebirds fledge and the white-tailed deer are having fawns. With warm season grasses, we’ll be able to delay harvest until later in the summer when young birds and mammals are older.”
Warm-season grasses are much hardier than cool-season grasses once they’re established (due to an incredibly deep root system), but they are delicate in the first few years. It also requires money, equipment, and considerable effort to switch to an entirely new type of crop: which is why this project has been in the works for so long.
Farmland Conservation
Bill McShea and Norm Bourg, ecologists at SCBI, are working with Maslanka on this project, which went into effect this summer. SCBI planted two fields of about 30 acres each, or almost a sixth of the hay fields, with warm-season grasses. These fields join two smaller plots of native warm-season grasses already growing at SCBI, and allow scientists to study the transition and establishment of the new grasses.
SCBI hopes these fields have an effect that overreaches the boundaries of the facility into the Front Royal and northwestern Virginia region. Bourg explains that he, McShea, and Maslanka have been working with a passionate group of local landowners and the Virginia Working Landscapes Grasslands initiative, which helps inform and equip landowners who are interested in protecting and enhancing habitat native to Virginia biodiversity.
Bourg says, “The intention is to have these fields be part of a network of public and private demonstration sites for landowners of modest means who are interested in biodiversity enhancement and conservation on their land. They’d be able to visit SCBI and other sites to see how to apply these management techniques themselves.”
The plan is for one of the fields to be actively harvested within three years, and its hay will be tested for nutritional quality and fed to Zoo animals. The other field will not be harvested, but managed as a wildlife diversity area where SCBI scientists can monitor the effects of the new species and management strategies on native wildlife. This management might include prescribed burning, which is the most effective way to rejuvenate warm season grass fields that are not being harvested.
“There’s a lot of progressive farming going on out here. We’re collaborating with local farmers and landowners to share what we are learning and learn what the local experts know, in order to improve habitat collectively,” Maslanka explains. “We’re trying to be model stewards of the land, and manage our land in the most environmentally responsible fashion we can, even in the face of seemingly competitive goals—such as agriculture and wildlife management.”
SCBI Front Royal is open to the public just once every year, for the Autumn Conservation Festival. It's your chance to see the facility and talk with SCBI scientists.
