Closing the Local Food System Loop

Category Archives:Food Security

Closing the Local Food System Loop

…by recycling poop.

For several years I’ve been working from a theory that we could be near a radical shift in our primary food production systems – an Agrarian Devolution. Barring the technological leap that brings on a cheap, abundant fuel source, or a massive drop in global population, the combination of high fuel, fertilizer and transportation costs and conservation challenges are making high input, centralized production and distribution less viable. If unhindered, economics will drive agriculture back to its agrarian roots of local production for local consumption. High input costs and high transportation costs should re-establish local food networks as the low-cost option in most areas.

Quality niche and specialty foods aside, the general populace still votes with their wallets. And despite a lot of lip service to local food, that vote is still very much for low cost, convenient options. It is a safe bet to assume therefore, that if (or when) local food starts to trump imported food on a cost basis (albeit with both at a higher nominal level than today) sales will surely follow.

Now, those with libertarian-leanings are probably thinking, ‘market signals will push our food systems back to the local level – stay out of the way and let it happen, end of story, get on with your life.’ But with the politics of food as it is, that shift may not be as simple as sliding along a supply-demand curve. Food is big business, with billions of dollars, rupees, yen, euros and yuan on the line. The existing multi-nationals have a vested interest in squeezing out expansion in local competition. And they have never been above lobbying governments to distort markets in their favour through twisting agricultural subsidy programs – the chief offenders being in the United States of America and the EU. Fifty years from now our food system could look the same as today, if governments are willing to squeeze their citizens for taxes to subsidize cheap food. Large-scale agricultural producers in some regions will continue to win, but the total number of farmers will decline, and small-scale producers would continue to live on the edge of going broke.

I believe, a little foresight and planning is needed to promote efficient, sustainable production. We need to level the playing field with public agricultural policies and support programs that focus on production efficiencies. That is to say, food production is worthy of some public funding, but don’t base that support on the total volume of output or the area in production, but rather the ratio of outputs to inputs. Expand a framework supporting a transition to lower input costs without greatly sacrificing production levels. And this should include closing the production loop in local agriculture systems by returning our food, human and agricultural waste streams back into food and energy production on much larger scale than is currently practiced. Close the loop, recycle your poop.

A few examples of what can be done with existing technology:

1. Mandate phosphorus recovery from every sewage treatment facility. Phosphorus is an essential element for crop production and coincidentally (or maybe not so much) one of the primary water pollutants in the western world. Humans contribute over 3 million tonnes of phosphorus annually to global septic systems. And many technologies already exist to recover phosphorus from sewage, including ‘mouse-trap’ cones developed at the University of British Columbia that pulls this valuable plant nutrient out of sewage effluent and creates a high-quality slow-release fertilizer. Local waste becomes a local resource.

2. Build the infrastructure to create biodiesel from algae fed on sewage water. There are already many private enterprises with viable systems to turn oils extracted from sewage-pond-grown algae into biodiesel. We can use carbon taxes on fossil-fuels to build a network of algae farms and biodiesel plants, and then sell back the fuel to agricultural producers and processors at cost without an accompanying tax. Incentives could also be given for farm-scale algae production ponds utilizing on-site manure and crop wastes to generate some or all of the on-farm energy needs. Again this turns an environmental liability into a production efficiency.

3. Use sewage sludge or waste water to fertilize farm forestry plantations. The trees then become a source of fibre for solid wood products or bioenergy, and can also be placed on-farm to serve soil and water conservation roles. A potential win-win-win solution.

And there are other practical options available too, including biogas generation or mandatory community composting programs that return that valuable humus to build soils. The important first step is removing any incentives that externalize the costs of waste generated in our food systems by letting producers and consumers pollute water with excess nutrients. And then through directed R&D and selective taxation, provide support to production, recovery and regeneration systems that operate at the highest efficiency.

More Edible Invasives – Vegetable Greens at Your Backdoor

Spring has sprung,
The grass has ris’,
I wonder where my backyard produce is.

Although the grass has not yet sprung forth in the corner of Great White North where I reside, it soon will be on the way. Spring is an excellent time to reacquaint yourself with the wonders of nature. And foraging for salad and cooking greens is not only a rite of spring, it also spices up one’s diet.

In a previous article (Edible Invasives – Eat Your Garden and Lawn Weeds) I covered dandelions, wild mustard, chickweed, lamb’s quarters, purslane and red clover. And by popular demand, I’ve assembled four more backyard ‘weeds’ that are also exotic epicurian edibles, guaranteed to add diversity to your diet, save you a few dollars on groceries and put you a few steps forward on a zero-mile diet. Many of these edible invasives are best consumed early in the growing season, as they can become bitter with age, making spring the best time to harvest.

First, in the interest of safety, let me reiterate my previous warnings on foraging for edible weeds:

  1. Not every weed is edible, and indeed, some are poisonous. Proper identification of prospective food plants is essential. If you have any reservations as to the identity, play it safe and don’t eat it.
  2. Always wash your greens before eating them and don’t pick any that have been directly or indirectly subjected to pesticides.
  3. Don’t eat plants from public boulevards, parks, playing fields, ditches, or any other area where you don’t know with certainty that they are free of unseen contamination.

With this in mind, why not try some of these edible invasives:

Stinging Nettle, Urtica dioica
The name doesn’t suggest a great food option, but stinging nettles, when handled and prepared properly, offer great spring fare. Stinging nettle is a perennial herb, growing up to 1-m tall from yellow-coloured rhizomes and stolons (underground stems). The strongly-toothed leaves, range from 3- to 15-cm long and are borne in alternating, opposite pairs on erect green stems. This nettle bears numerous small green to brownish flowers in dense bundles. The leaves and stems are very hairy with both non-stinging and stinging hairs. The nettles contain chemicals that can sting and irritate. Wear gloves and long-clothing to prevent skin contact during harvest and handling. Nettle leaves are delicious cooking greens and are rich in vitamin K. Gather young leaves before plants reach 30-cm tall. When mature, nettle becomes increasingly tough and inedible. Cooking destroys the stinging properties of the nettles. Try using nettle as a replacement for spinach in spinach soup recipes.

Stinging Nettle


Common Plantain, Plantago major
This common lawn and roadside plant sends up groups oval, dark green leaves, 10-cm long, from short, tough rootstock. The leaves are thick, strong and fibrous when mature, with 3 to 7 or more ribbed veins extending from a long reddish leaf stalk (aka the petiole). Harvest young leaves early in spring before they thicken and become stringy. Leaves can be eaten raw in salads or boiled, blanched, steamed or sauteed.



Sheperd’s Purse, Capsella bursa-pastoris
This garden and pasture weed looks somewhat like wild mustard, and has the same sharp, peppery taste. The lobed-leaves grow in a basal rosette. Stems emerge from this base and grow between 20 and 50 cm tall, and bear a few pointed leaves which clasp around the stem. Small, white flowers produce distinctive heart-shaped seed pods. Only use early spring growth – these plants become increasingly bitter-tasting with age. Sheperd’s purse is a popular cooking herb in China, Korea and Japan. Try it sliced and stir-fried with a mix of other vegetables and mushrooms.

Sheperd's Purse


Common Meadow Violet, Viola sororia
These tiny 4 to 10 cm tall, perennial plants appear stemless, because leaf stalks emerge from below ground level. The heart-shaped leaves are hairless and have rounded teeth along the margins. Purple or occasionally white flowers form on leaf-less stalks. More common in eastern North America, these free seeding plants are one of the earliest spring flowers in many areas. Both the flowers and leaves are edible and can be used when young in salads or as garnish. Candied violet flowers can be made by preserving newly opened blooms with a coating of egg white and crystallized sugar.


Community Forest Gardens

Food security is a growing concern. And not just over access to food, but access to healthful food. And rightly so. Global food systems are once again feeling the tremblings of supply interruptions stemming from grain export bans in Russia and poor harvests due to drought and floods elsewhere. Similar to the international price shocks, hoarding and limited rioting that occurred in 2008 in the face of wheat and rice shortages, we may be in for another round of inflation in food costs and heightened food security awareness this quarter.

Few things can provoke a stronger instinctual response than the prospect of food shortages. So it is not surprising that many people are becoming cognizant of how vulnerable our food systems are to the interruption of global supply chains. Price inflation and growing concerns about the quality and safety of our food supplies have also been motivational for a rapid expansion in community gardens all around the globe. Not only do these co-operative projects provide the landless and land-poor (though not necessarily lacking resources) with an outlet for a great outdoor activity with mental health benefits, it also helps to reconnect an increasingly urban populace with food production, and the opportunity to supply themselves with nutritious food of their choosing.

Building capacity and access to community gardens is of benefit to everyone. To be clear, I don’t think they’ll contribute greatly to global food supplies in the short term. But the individual and social benefits of participation, however small, in sowing, tending and harvesting some of your own food are immeasurable. And I also believe that agroforestry, specifically through forest gardens, has tremendous potential to complement the community garden movement.

I have previously extolled the virtues of forest farming, and firmly believe it will be a production system of prominence in the future. Within the family of forest farming practices, forest gardening can best be described as food systems replicating the patterns and processes of natural forest ecosystems. Forest gardens are a structured polyculture of food plants combining multiple canopy layers of fruit or nut bearing trees, and shrubs, herbs and vegetable beds into synergistic and sustainable production units. Utilizing applied ecological principles to minimize competition and promote facilitation through companion planting, forest gardens are efficient, productive outlets for inter-cropping.

The potential benefits of incorporating forest gardening into the community garden movement are many fold: enhanced productivity, conservation and aesthetics, and all within confined spaces.

Many community gardens are located in small urban spaces and expanding production vertically with shrub and tree canopy layers makes good sense to maximize the efficiency of food production per area.

Trees and tall shrubs can also function to mitigate some of the less pleasant aspects of city life. They dampen noise, trap pollutants, dust and odours. Trees cool and moisten the summer air and, when of sufficient size, will shelter adjacent buildings from hot and cold, decreasing the need for air conditioning and heating, respectively. And forest gardens also can serve as functional park and conservation areas; giving refuge to small birds, butterflies and other wildlife, building soil, and adding positively to the visual landscape while still contributing to local food production.

Community forest gardens can therefore fulfill the all the roles of community gardens in reconnecting urban residents with food production and contribute to community food security, and they also make the best use of available space and can be a source of ecological goods and services and visual aesthetics in the concrete jungle.

I’d love to hear from anyone who already participates in a community forest garden program or is planning one. Please share your story in the comment form, or send me a note via my contact page or Twitter.

Diversification is the Only Free Lunch

Question: When does a housing development in St Petersburg, Russia threaten the future of Canadian agriculture? Answer: When it paves over the world’s largest repository of fruits and berries adapted to northern climes.

Conservation and food security activists have been called to arms over plans to develop upscale housing on the Pavlovsk Experimental Station near St Petersburg. The Pavlovsk Station houses a large, unique collection of horticultural genetic resources: strawberries, gooseberries, cherries, raspberries and many other small fruits. Totaling more than 4,000 varieties, the collection includes almost 1000 types of strawberries from which most modern commercial varieties are derived. Approximately 90% of the germplasm at Pavlovsk can be found nowhere else. The importance of this collection to plant breeders, particularly those in the boreal through temperate zones, can’t be overstated. This diverse pool of genetic material is needed to develop new varieties adapted to the ever changing complex of diseases, pests and climate variability that can threaten our food supplies.

This is yet another example globally of how we undervalue the biodiversity that is fundamental to our food, fibre and increasingly bioenergy supplies. And lest anyone accuse me of unfairly singling out our boreal brethren in Russia, Canada has no stellar record when it comes to concrete actions for preserving agri-diversity and cropping options. Case in point, in the interior of British Columbia where I reside, Agriculture and Agri-food Canada long ago closed the agricultural experimental station in Prince George in the name of austerity. The reasoning for terminating the only regional agricultural research support was that this area was on the fringe of agriculture and was well supported economically by the forest industry. Now in the wake of the the mountain pine beetle epidemic that is laying waste to a portion of BC’s forest industry, community economic development organizations are scrambling to reassemble regional support for the agricultural sector to help strengthen and diversify the economy. And they are finding that cropping resources and options, particularly for permanent agriculture, are limited.

And for those Canadians and others that somehow missed the lesson on the need for diversification that the mountain pine beetles have provided, spruce budworms or Douglas-fir bark beetles may soon be providing a refresher course.

The time to diversify is when you least think you need to, not in the middle of a crisis when resources will be stretched or gone. Agriculture in the north has not suffered a major production collapse on the scale of the pine beetle impacts to the forest industry, but the conditions for developing disaster always lurk on the edges. Temperature and precipitation patterns are shifting. New disease and pest outbreaks that can colonize a warmer future are a real possibility. We’re are already seeing new populations of spotted wing drosophila that could smack down our multi-million dollar berry industry. Oak wilt disease also has a foothold in Canada and is moving northward. The fallout from mad cow disease has sent the cattle industry into a decade-long downturn.

I can’t tell what the future holds for agriculture in the north (or the middle or south for that matter), but changing climate, pest and market uncertainty all point to the need for flexible, diverse production systems. Investing in preserving crop diversity and agricultural adaptation is an investment in managing the risks to food security, community and economic stability.

As a Vladamir Lenin look-a-like on the financial network CNBC is fond of repeating to the investment community: “Diversification is the only free lunch.” And so it also goes for the agriculture sector. Preserving and culturing diverse production opportunities will greatly lower the risks to agricultural producers and interruptions to global food supplies. And it starts with concrete actions at the regional level to preserve and expand the genetic diversity on which agriculture is founded.

Edible Invasives – Eat Your Garden and Lawn Weeds

Are you distracted by dandelions? Perturbed by purslane? Stressed by sorrels? Don’t spray and pray your garden and lawn weeds away. Pull out your fork and enjoy the bounty of exotic edible greens at your doorstep.

Many of the common weed species that have infiltrated North America are introduced plants from Eurasia. Some of these ‘weeds’ have long been sought out as tasty, nutritious additions to summer fare in both the old country and new. They can add welcome variety to ordinary salads, or as steamed or stir-fried greens, and are often packed with nutrients and healthful phytochemicals.

What follows is a brief introduction to some common, and easy to identify, edible lawn and garden invaders that I’ve eaten.

Before diving into the details though, I feel compelled to warn the casual back-yard forager that not every weed you will encounter is edible, and indeed, some are poisonous. Proper identification of prospective food plants is essential. If you have any reservations as to the identity, play it safe and don’t eat it. Always wash your greens before eating them and don’t pick any that have been directly or indirectly subjected to pesticides. And don’t eat plants from public boulevards or out of ditches, as you can never know with certainty if they are free of unseen contamination.

On to the greens…

Dandelion, Taraxacum officinale
This ubiquitous, perennial lawn weed, springs forth a circle of elongated and irregularly-toothed, dark-green leaves from a deep, carrot-like taproot. Bright yellow flower heads are borne on ends of long, smooth, hollow stalks that arise from the middle of this rosette of leaves. When mature, the flowers are replaced by seeds tipped with a tuft of white hairs allowing them to parachute through the air. Both the young leaves and flower buds of dandelion are great in salads or on sandwiches or lightly steamed like spinach.



Wild Mustard, Sinapis arvensis
This annual weed of gardens, fields and pastures grows from 30- to 100-cm tall and is identifiable by the clusters of bright yellow flowers with four petals arranged in a cross pattern. The young leaves have a slightly rough texture, and sometimes with coarsely toothed and indented edges. The undersurface of the leaves have small hairs along the leaf veins, with slightly longer, stiff hairs near base of the stem. If crushed the leaves emit a familiar ‘mustardy’ smell. Harvest only the early-growth leaves. They have a sharp, peppery taste and are good raw for spicing up a mixed vegetable salad. As a cooked green, wild mustard pairs nicely with bolder-flavoured meats. I enjoy mustard greens with pork or bison. The young flower buds of wild mustard can also be eaten raw or steamed like broccoli.

Wild Mustard


Chickweed, Stellaria media
Chickweed’s many branched stems spread close to the ground and can grow over 30-cm long. Stems are covered by bright green, 1- to 2-cm long, pointed leaves that form in pairs. This annual lawn and garden weed is delicious raw as a salad green, especially when the tender tops are harvested.



Lamb’s quarters, Chenopodium album
Somewhat variable in appearance because of plastic stem form. Lamb’s quarter can be recognized from its triangular (wedge-) shaped silvery blue-green, leaves that have a wavy indentation along the edge and somewhat resemble those of its botanical cousin, spinach. Flowers are very small, green and grouped together in clusters at the tip of the plant. This garden weed can grow more than 2-m tall on rich soils. When young and small (<20 cm) the whole plant is tender and tasty. Upper (newer) leaves can be picked continually from older plants and eaten raw or steamed in the manner of spinach. Lamb's quarters


Purslane, Portulaca oleracea
A common, ground-hugging garden invader forming circular mats up to 60-cm in diameter if you really get behind on your weeding. It has thick, succulent, deep-green oval leaves on reddish and equally watery stems. Leaves and stems can be eaten raw or cooked, and the leaves can be frozen or pickled for storage. Purslane is noted as a rich source of dietary iron. The flavour is reminiscent of lemon and it is also a good source of omega-3 fatty acids. It also has okra-like, gelatinous qualities when cooked, and so can be used to thicken soups and stews.



Red clover, Trifolium pratense
Edible properties aside, it baffles me why anyone would want to nuke a nitrogen-fixing plant from their lawn. Yet some still consider this short-lived, perennial legume a weed. It has a weak central tap root with numerous fibrous side branches. As its scientific name indicates (“Tri-folium”), leaves form in groups of three on the numerous stems that rise from the root centre. Tiny red to light purple, pea-shaped flowers are crowded together in a dense globe-shaped flower head which emerges from the tips of the branches. Clover flowers and leaves are rich in vitamins and add exotic-tasting variety to mixed salads or when cooked into soups and stews. The closely related white clover (T. repens) has a milder flavour but is similarly good raw or cooked.

Red clover

All these and many more edible invasives add credence to my belief that weeds are merely plants whose virtues have yet to be discovered. Or in the case of plants introduced from afar, virtues that have not yet been rediscovered. Add these backyard greens to your diet and you may soon be regretting all the sod grass getting in the way of your wild salad bar.

Read about More Edible Invasives here

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