Hedgerows – Letting Nature In

Posted by: Arthur’s Point Farm

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February 14, 2024

What's a Hedgerow?

Hedgerows are having a moment due to growing interest in sustainable farming and ecological stewardship. They simultaneously serve many different purposes and have existed in agricultural landscapes for millennia. The USDA defines a hedgerow  as the “establishment of dense vegetation in a linear design to achieve a natural resource conservation purpose.” The intended function will determine its design and species composition. In addition to their utilitarian functions, hedgerows can be designed to provide diverse habitat for wildlife.

Above is a video flyover from July 2023 of a three year-old hedgerow at Arthur’s Point Farm, including American linden, honey locust, red maple, red mulberry, black locust, and hybrid poplar. We planted this 800 foot long row of trees as a windbreak between two pastures used for grazing livestock. The intention is to provide shelter, shade, and fodder for the animals, to protect the pasture from drying out, and to create a biodiverse ecotone for wildlife and climate resilience on the landscape. 

Hedgerows Provide Essential Wildlife Habitat

Hedgerows integrate nature into managed spaces, enhancing biodiversity while also providing many utilitarian uses. When planted at least twenty feet wide, they can serve as corridors for wildlife to move through less hospitable landscapes. As these corridors reach maturity, they can lead to profound changes in the landscape and the habitats they support. Where any two distinct habitats meet, one finds valuable environments known as ecotones. Ecotones “do not simply represent a boundary or an edge; [but] the existence of active interaction between two or more ecosystems with properties that do not exist in either of the adjacent ecosystems.” 

Hedgerows provide “zones of intermingling” that support a wider array of species than do areas with less biodiversity. While a forest or a meadow each serve important ecological functions, the space in between can provide an abundance of habitats for many species of plants and animals. These zones provide refuge for wildlife and enhance the resilience of the landscape.

The ecological benefits associated with planting hedgerows are not limited to those stewarding agricultural land or large pieces of property. There are many ways to provide habitat, and the best way to do that is to prioritize planting native species at whatever scale. We recommend Douglas Tallamy’s Bringing Nature Home for an in-depth argument promoting native species.

Hedgerows Support Sustainable Agriculture

While enhancing biodiversity, hedgerows also have many utilitarian functions that benefit farmers and make agriculture more sustainable. These include providing shade and forage for livestock, protecting fields from wind and desiccation,  reducing chemical drift from nearby fields, delineating boundaries, and carbon sequestration. A  hedgerow planted to break prevailing winds can even help to reduce heating bills of protected buildings.

When hedgerows are planted to slow down wind velocity and limit soil erosion, they’re called windbreaks. Their efficacy is contingent on density and species selection. If a hedgerow is established to protect livestock and/or structures from wind or to serve as a screen for sight, sound, or chemical drift, density of over 60% is recommended.

Windbreaks are valuable for cultivated open lands and pasture, as disturbed soils are highly erodible from forces of wind. They also protect orchards from harmful winds. By slowing the force of the wind around an orchard and preserving pollen concentration in the area, windbreaks enable more pollination and fruit set. Windbreaks planted with intentionally chosen species will also provide shelter for native pollinators that can assist in pollination. For crop and soil protection, a density of 30-40% is recommended.

The height of chosen species at maturity should be considered in designing a hedgerow. Windbreaks will shelter an area proportionate to its height, and its efficacy will diminish at a horizontal distance of thirty times its height. For example, a hedgerow ten feet tall will protect an adjacent field from wind only within three hundred feet of the windbreak.

Trees & Shrubs for Hedgerows in the Northeast

A well-established hedgerow can last for generations. Since we’re focused here on bringing nature into our cultivated landscapes, it’s important to emphasize a diversity of native species. Here are some great hedgerow tree and shrub species (native to the Northeast) grown in our nursery, available at our online shop.

Eastern redbud (Cercis canadensis) is an all-around favorite on our the farm. It’s important to pollinators as its flowers provide some of the earliest forage for our native bee species (e.g., bumble bees, mason bees, cuckoo bees, long-horned bees, mining bees, and sweat bees). Redbud can thrive in a wide array of habitats, including shady areas. Relatively short-lived, Eastern redbuds typically begin to flower within the first few years of establishment. Young seed pods, high in vitamin C, can be eaten by humans, livestock, and wildlife, and the flowers can be eaten raw or fried. If you’re a citizen-scientist, learn more about how to participate in the The Redbud Phenology Project here!

American hazelnut (Corylus americana) can also fill an important niche in a hedgerow. Its shape and size helps to increase the overall density of the hedgerow, an integral part of mitigating high winds. American hazelnut provides important cover for wildlife and its late summer nuts are extremely popular with neighborhood critters. If you can beat them to it, people enjoy these small and tasty nuts, too. While not a full native species, a hybrid hazelnut (C. spp.) serves a similar function to the American hazelnut. Nuts from this hybrid are likely to be larger than the C. americana listed above, but since it’s grown from seed, there is variability in the nuts produced. Hazelnuts prefer full sun and moist, well-drained soils, but will tolerate part-shade and drier conditions. Hazels will produce fewer nuts in shadier sites.

In mid-spring, a blooming hawthorn (Crataegus phaenopyrum) buzzes with pollinators and hummingbirds. Its abundant berries provide winter forage for birds and people: they can be used for jellies and are high in antioxidants. Its thorns protect nesting birds and provide larval habitat for the Gray Hairstreak (Strymon melinus), Red-spotted Purple (Limenitis arthemis astyanax), and Viceroy (Limenitis archippus). Adaptable to a wide range of soil conditions, including pH, hawthorn tolerates urban pollution and clay soils.

Native Birches

Yellow birch (Betula alleghaniensis) and Sweet birch (B. lenta) fill similar roles, though each requires specific site considerations. They can grow to be 70 or 80 feet tall but are typically more compact and can often be found in transition areas between managed landscapes and woodlands. Exfoliating bark provides habitat for insects, and birch seeds provide important forage for many birds. Birches also support a variety of caterpillars and moths, provide medicine for people, and can be tapped for sap.

Native Willows

The willow genus, Salix, consists of a variety of trees and shrubs. Fast-growing and generally flood tolerant, willows are effective in stabilizing stream and pond banks and host several butterfly, moth, and beetle species. Pussy willow (S. discolor) (top left) works well in riparian areas and Sandbar willow (S. interior) (top middle) is valued for its drought and flooding tolerance. Both grow in shrub-like habits, these species are great choices for quickly establishing greater density in lower horizons of a hedgerow and for providing groundcover for wildlife. Black willow (S. nigra) (top right) is a native alternative to the recognizable weeping willow and is well suited for very wet soils.

Hedgerows Define Ancient Landscapes

Hedgerows, or hedges as they’re known in the United Kingdom, have been planted for many centuries, mainly as natural fencing for livestock. These ancient hedges create semi-wild ecotones that are invaluably integrated into human landscapes. One in particular, Judith’s Hedge, is thought to be at least 900 years old. Hedges can survive this long when actively managed, and styles of doing so vary by region, but all are based in promoting regeneration. For those interested in learning more, the National Hedgelaying Society details the history and different styles of hedgelaying. Though these hedges are different from the wider, more diverse hedgerows discussed here, they illustrate how even a narrow strip of vegetation can create valuable human benefits and important ecotones that support a diversity of wildlife.