biodiversity – Champlain Valley Crop, Soil & Pasture

How to Restore Their Perceived Value

By Cheryl Cesario, UVM Grazing Specialist

Scott Bauer / Photo courtesy of USDA Natural Resources Conservation Service, via Wikimedia Commons

A recent study published in the scientific journal, ‘Nature’, examined the importance of species diversity in grassland ecosystems. The German-based study included dozens of researchers collecting data along various levels of the grassland food chain. The data was collected on a total of 4600 species, the most extensive ecological sampling in Europe to date. These species, they found, interact and rely on each other to provide critical grassland ‘ecosystem services’, such as food production, soil development, carbon storage, and flood and drought mitigation, among other climate regulatory functions. The study emphasizes the importance of maintaining biodiversity across all levels of the grassland food chain, which provide synergistic effects that ultimately benefit the planet and humanity as a whole.

So if grasslands play such a critical role in our planet’s health, why are they disappearing at an alarming rate? The same month the ‘Nature’ study was published, the Union of Concerned Scientists published an article about the continued reduction of grassland acres across the U.S. From 2008-2012, extensive acreage was cultivated for the first time, mostly planted to annual crops. This phenomenon was greatest in the Great Plains and western Corn Belt, where 77% of new cropland was borne from grasslands. Several crops took their place, led by corn, wheat and soybeans. These grasslands are being traded for crops that require irrigation in areas where irrigation and drinking water supplies are shrinking.

Contrast this with the ‘Nature’ study regarding the importance of grassland biodiversity and the role these ecosystems play in climate adaptation. The regions of the country with the highest loss of grasslands are also the same ones where flooding frequency has increased the most. This doesn’t seem like the best strategy for building resiliency.

There are USDA programs designed to encourage and protect grasslands, such as the Conservation Reserve Program (CRP). CRP encourages farmers to convert highly erodible cropland or other environmentally sensitive acreage to vegetative cover, such as native grasses, wildlife plantings, filter strips, or riparian buffers. Farmers receive an annual rental payment for the term of the multi-year contract. However, enrollment peaked at 36.8 million acres in 2007, dropping to 24.2 million acres by September 2015. States such as Kansas, North Dakota, Montana and Texas have seen reductions of over 1 million acres each in CRP land over the past 8 years. For scale comparison, in Vermont our CRP acres total approximately 2,800 acres, mostly in various riparian buffer, filter strip, and habitat plantings. While we don’t have large swaths of native grasslands here in Vermont, we do import large amounts of grain from the Midwest to feed cattle and other livestock, so ultimately we are part of the grassland-biodiversity-climate adaptation issue.

When commodity prices are high, acres that transition out of the program are often not re-enrolled. The trend may continue: between 2020 and 2022, 11.6 million CRP acres are scheduled to expire nationwide and it remains to be seen what the future holds for those grassland acres. With more and more discussion and interest in adaptive, resilient and regenerative agriculture, one would hope that more policies and programs may be on the horizon to encourage biodiverse grassland ecosystems that provide so many benefits.

Schuessler, Ryan. “The enormous threat to America’s last grasslands.” The Washington Post: Energy and the Environment. June 16, 2016.

Do you have questions about grazing management? Contact Cheryl Cesario [802-388-4969 ext. 346 or cheryl.cesario@uvm.edu]

Improving plant biodiversity in pastures has several benefits. A variety of species in a pasture will give grazing animals a range of plants to eat and provide a buffer against weather and seasonal variability. A combination of grasses, legumes and herbs will provide a mix of shallow-rooted and tap rooted plants, the latter of which will create channels into the subsoil and bring up necessary nutrients. A healthy pasture ‘polyculture’ results in a healthy soil ecosystem, improved water percolation and reduced run-off, which in turn benefits our streams and lakes.

So, how do you improve pasture diversity? One option would be to utilize the no-till drills that the UVM Extension office has purchased and incorporate the species of your choice into your pastures. Seed may be incorporated at 8-14 pounds per acre. An example might be 8 pounds of orchard grass, 4 pounds of ladino clover, and 2 pounds of chicory per acre. Chicory? Yes, but let’s clarify we are talking about forage chicory, which is not the same plant as the one seen growing on our roadsides. Forage chicory is a great plant for mineral nutrition in livestock and is highly digestible. If the goal is to add some legumes to pastures that tend to be on the wetter side, drilling in birdsfoot trefoil or alsike clover may be beneficial. On drier ground, with a neutral pH, alfalfa may be a good choice. Red clover is adapted to a wide range of soil types and is fairly easy to establish either through interseeding or frost seeding.

While there are dozens of commercial pasture seed mixes on the market, they are not all created equally. It’s important to read the seed tags and in many cases more information can be found online. For example, the website for the company of one mix that has been sold locally says, “In climates lower than Zone 4, plants may not overwinter. Persistence can be greatly increased if plants are insulated by snow cover.” Although we are in Zone 4 in the Lake Champlain region, a mix like this may only be marginally hardy here, especially when we have a winter with little snow. Always check that the varieties listed in a commercial mix are appropriate for our climate.

An example of this would be the perennial ryegrasses. It is preferable to select the ‘diploid’ rather than the ‘tetraploid’ varieties, which will increase winter hardiness. This terminology will usually be indicated on the seed tag. Tall fescue is best avoided, as it has palatability issues due to the presence of internal fungi that produce alkaloids. Tall fescue is often found in seed mixes developed for warmer climates. Meadow fescue, however, is a good choice as it is more digestible and is also more winter hardy.

One mix that we have had success with on our farm is a grazing mix described as ‘an excellent choice for high producing dairy livestock and grass-finished beef’. It contains 30% perennial ryegrasses, 30% grazing tolerant orchard grass, 25% meadow fescue, 7% medium red clover, 6% Alice white clover and 2% forage chicory. It’s a great all-around mix with grasses, clovers and the added bonus of the chicory.

Tag: biodiversity

Biodiverse Pastures