Monday, November 24, 2014

Designing a Permaculture Hedgerow


Last night, I had the opportunity to join in a permaculture discussion where hedgerows came up, and people who know me know that I'm crazy about hedges. As modern agricultural research turns towards perennial crops, and polyculture plantings, the hedgerow stands out as a traditional and uniquely adapted system for utilizing both. Better still, these woody perennial polyculture systems can do extra work by providing building and craft materials, ample carbonaceous material for composting, providing windbreaks, wildlife shelter, fences for wildlife, create fire and erosion barriers, provide forage, protect livestock or humans, and greatly increase the biodiversity that has a positive benefit on pest and disease problems and system health and resilience. 

Far more than mere shrubbery, hedgerows represent the original "food forest" technology of cold temperate climates, with their linear nature being a perfect adaptation of forest gardening to northern latitudes where light penetration becomes key. And since forest gardening has been called "the world's oldest land use" by anthropologists, it's no wonder that where you find hedgerows they're fundamental to cuisine, medicine, magic, shelter... and life in general.

If the hedge-bug bites you, you can delve deeply into our cultural heritage with a Google quest across the the rich topic of the Hedge, by exploring:
Hedgemedicine
Hedge-laying 
Hedge-witchery/Hedge-wizardry
Hedgerow foraging
Tapestry Hedges
French Hedgerows in WWII
The Hortus Conclusus

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At Lillie House, our research into hedge-tech has focused on adapting the traditional systems of British and French hedgerows, especially the English "cut and lay hedge" and the French "woven hedge" to the Great Lakes region by using bio-mimicry of the spontaneous, natural hedge-like systems that arise throughout the region. Some of our favorite foraging areas have been these natural hedgerows and we've aimed to study and recreate them at our home.



A generalized European planting would typically use:
A "thorny" main structural planting of 60% Hawthorn or Blackthorn (wild plum) or 30% of each of those. In addition to thorns, these species spread by sucker to fill in dead sections, and take very well to "coppicing," and creating tight woven hedges. 
10-20% Hazel. Hazel was sometimes used as the "main planting," especially in more urban areas where nuts were desirable and 
And a mix of: roses, brambles, elder, crab-apples, damsons, sloes, and wild apples and pears.
Hedgerows intended as wind breaks might include 10-30% evergreens, including yew. Science has verified the wisdom of this traditional approach, finding that a greater density of evergreens increases the turbulance of winter winds, actually increasing the problem instead of reducing it.

To get an idea of these plantings, try looking at some of the offerings of the many British companies selling traditional Hedgerow plants:


For the Great Lakes region, many of these plants could be adapted at least in function, though Blackthorn may experience problems with black rot. Good substitutes for the primary planting could include Sea Buckthorn or Goumi, which both fix nitrogen and coppice well. 

Our US wild plums do not generally coppice well, so they aren't good choices, however other prunus species like Nanking Cherry make good substitutes. 



Rugosa roses make an excellent choice for the US, as do our native elders. Blackberries  or wild black raspberries would also be quite at home in such a planting. Mulberries are commonly found in natural hedgerows here, and I suspect that after some extra work to get it established, Paw Paw would be very happy with life in a hedgerow, too, as it suckers, tolerates shade and takes to coppicig well.  

Through your next drive through the country, a quick look out the window and you're likely to see exactly this kind of plant community growing wild in the ditches. One even happens to be growing along the bike trail down the street for us, which is the one we copied for our planting. There are probably several near your home that could serve as the basis for your hedgerow. 

But not all trees will work well. French and British models typically excluded trees that would be allelopathic (toxic to other plants) or those that quickly sucker and are very tolerant of shade, as they become weedy in a hedgerow. Norway maple, willows, certain dogwoods, and even English elder (a stereotypical Hedgerow tree) were often avoided, depending on the site. Tall trees such as oak, linden and maple were often included, but spaced at least 2 or 3 times mature orcahrd spacing, perhaps 200' apart. These rules typically aimed to keep hedge maintenance low by reducing pruning and weeding. 

Once you have your trees chosen, you'll have a wide variety of perennial vegetables and fruits that are ideally suited to the conditions of a hedgerow. At LillieHouse, these include: strawberries, sea kale, asparagus, good king henry, sorrel, endive (chicory) nettles, poke, comfrey, stinky bob, perennial alliums (we have over a dozen varieties) cleavers, milkweed, turkish rocket, sweet rocket, jerusalem artichokes, japanese yam, grapes, kiwi, ground nut, ground pea, ladies thumb, clover, salad burnet, spring beauty, mints, and many others! Hedgerows naturally take advantage of "edge effect" making them an ideal place for a huge variety of species. 

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Once you have an idea about what plants you want in your hedgerow, you'll need to make a plan for establishing it. Like all things in appropriate technology, traditional technology and Permaculture, the trick here is finding the right balance of "intensive" and "extensive" tools for the job. Traditional European hedge systems provide us with a wide range of options here, from the careful and deliberate plantings of urban French Tapestry Hedges to the nature-assisted systems of "dead hedging." 



Any one hedge is likely to use a mix of hedging approaches, but arranging them in order of intensive to extensive, they might look like this:
1. Intensively planted urban or "zone 1 or 2" hedges close to the home: Hand planted at high density around 1-2' apart, relying on selected short tree species chosen to give a yield of fruit, nuts, berries beautiful folliage and flowers. Shorter species make the hedgerow less labor to maintain.  
2. Semi-intensive: hand-plants pioneer species like elder, prunus species, and hazel at a greater distance of 3-5' or more. Birds, mamals, and suckering fill in the hedge. Oftentimes, hedge-layers would encourage the process by throwing fruit cores and seeds into the hedgerow. 
3. Sacrificial planting: very fast growing trees are planted at a useful density 2-3' and quickly woven into a hedge. Later, these trees are selected out as more desirable species fill in. Trees especially suited to this might include empress tree, toon tree, and hybrid poplar.
4. Dead hedging: using available materials, pruinings and fallen wood to build a temporary fence to meet your needs. Over time, perching birds, and mammals help fill in the planting, reliably creating a hedgerow of useful mast and fruit species. The hedge-layer can help the process by occasionally planting in a few desirable species and selecting for the best plants. 

One of my favorite gardening blogs has a great post on how this mix of procedures is covered in the French literature here: 


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And finally, if you've come this far into hedge-geekery, thanks for your time! You can find even more info on our hedgerows by searching this blog, if you like. Better yet, take a minute to look at some pictures of these traditional French and British systems:

1. Google search for British "hedge laying."

2. French tapestry hedges:

And finally, if you're planning a hedgerow, please drop me a comment and let me know about it. As a certifiable hedge-geek, I'd love to hear about your project. 

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