I've admired hedgerows from afar - marveled at how they're constructed and their natural beauty. They have a certain romance in my mind. I've imagined the hedgehogs and English hares that live in them, even though I've never seen either of these creatures in nature. There aren't hedgerows in the part of Pittsburgh I grew up in.
But I am a big fan of what I have referred to in my Landscape Design practice as a "mixed screening border". It turns out that a mixed border is not so far from what a hedgerow is.
Hedgerows are most often seen in Europe where they are typically used to line field borders and contain livestock. They provide a long list of benefits wherever they grow.
Hedgerows differ from hedges in several ways. The goal is not a uniform look, but instead a diverse planting of a number of species of woody plants, from shrubs to small trees, along with herbaceous groundcovers at their base, all chosen with similar demands of soil type, moisture, and sunlight. Hedgerows are layered plantings, with an occasional small tree rising up above a mixture of shrubs, some of considerable width, others with tall arching stems under-planted with lower shrubs, so that every available space is covered in growth. The layers of plants mimic a woodland or forest edge. Planting a mixture of native, mast-producing shrubs along with evergreen conifers will ensure suitable shelter, nesting sites and food sources for a wide variety of wildlife throughout the year. Hedgerows create a tremendous amount of habitat while leaving little space for opportunistic weeds to grow.
With proper plant selection, these mixed-border-hedgerow-habitats can include native plants that provide nectar, pollen and larval food for pollinators as well. Birds will be attracted to the berrries and will have opportunities to find safe nesting sites. Areas within the hedgerow can be suitable for ground-nesting bees as well.
Hedgerows can provide not just habitat but also privacy. They can define property lines, screen unsightly views, minimize erosion, reduce sound pollution, and buffer strong winds. They're a great way to add "wild" to the suburban landscape
Young forest, also known as shrubland, is an early-successional habitat usually present due to a disturbance such as clearcutting, abandonment of farmland, fires, or floods. Shrubland is typically defined as sites with persistent shrubs and/or seedling to sapling sized trees. With a temporary nature, young forest only lasts about 10-15 years before growing into more mature forest without any further disturbance.
A whole class of birds depends on shrubland habitat for suitable nesting sites - they nest in low shrub-dominated habitats with little or no tree canopy cover, and are unable to establish territories and nest in closed canopy forested habitats.
Shrubland is one of the most endangered ecosystems in the Northeast - a further contribution to loss of bird diversity in our world. That's because land management practices that maintain early successional habitat are complicated and labor-intensive. A hedgerow, on the other hand, is much like an early successional habitat but easily maintainable as part of a suburban landscape.
Hedgerows can be the way to seamlessly integrate a Pollinator Strip into your landscape - even if you don't have a vegetable garden or a farm. The flowering perennials can become part of the design. Creating high quality habitat for pollinators provides a source of nectar for adult pollinators, a diversity of herbaceous material for immature pollinator life stages, and herbaceous material for nesting. Additionally, adult bees need diverse flowering plants from which they can collect pollen to feed to larval bees.
Pollinator habitat also can support other beneficial insects, such as predators and parasitoids that attack crop pests, if bunchgrasses are included. To be most abundant, these valuable insects need alternative food sources when their prey is lacking. Increasing the abundance of flower nectar or pollen helps them to live longer, lay more eggs, and produce more offspring.
Grasses provide overwintering shelter for a diversity of predatory invertebrates, especially ground beetles that contribute to the suppression of crop pests such as aphids, slugs, snails, caterpillars, and the larvae of herbivorous beetles like Colorado potato beetles.
Some farmers have started planting "beetle banks" next to their fields to support biological pest control: linear strips of perennial native bunch grasses planted on a berm within or adjacent to fields. Berms are used to promote good drainage as well as to make it easier to mow and harvest without disturbing them. The beneficial insects are close to the crops and don't have to expend as much energy to find the aphids.
I think the term "Hedgerow Habitat", coined by Kris Wetherbee in the May/June Issue of The American GArdener magazine in 2016, perfectly describes the diverse functions these types of plantings provide.
I'll be installing some this season for sure!
