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Check out my recent interview on IT’S ALL ABOUT FOOD podcast with Caryn Hartglass

Since 2009, It’s All About Food, has been bringing you the best in up-to-date news regarding food and our food system. Hosted by Caryn Hartglass, a vegan since 1988, the program includes in-depth interviews with medical doctors; nutritionists; dietitians; cook book authors; athletes; environmental, animals and health activists; farmers; food manufacturers; lawyers; food scientists and more. Learn about how we can solve many of the world’s problems today and do it deliciously, here on It’s All About Food.

Stream It in a new window or check out the entire transcript HERE.

On the show I talked about Project Drawdown, a recent collaboration that was edited by Paul Hawken. The book includes looking at comprehensive climate solutions including carbon farming, renewable energy, girls education and more!

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Carbon Farming Practices

What farming practices can help stabilize the climate by sequestering carbon? Almost anything that builds soil organic matter can do the trick, but some sequester much more carbon than others. Even low rates of carbon sequestration can make a huge difference if practiced on enough farms. Here’s a typology and comparison of these systems. Note that a hectare is roughly 2.5 acres. To learn more check out my upcoming workshop at the carbon farming course! Early registration ends December 15th.

Improved Annual Cropping Systems

These practices make our production of annual crops more carbon-friendly. These systems sequester low amounts of carbon, typically 1-2 tons per hectare per year. Their big advantage is they allow us to grow the crops we know and love, and we already have equipment and infrastructure for production, processing, and consumption. Some are already widely practiced, like no-till (111 million hectares), organic annual crops (6.3 million) and system of rice intensification (4-5 million farmers globally). Other practices include crop rotation, green manures, cover crops, use of compost, and mulching.

Organic no-till system developed by Rodale Institute. Image courtesy Rodale Institute..
Organic no-till system developed by Rodale Institute. Image courtesy Rodale Institute.

Perennial-Annual Systems

These systems integrate perennial elements like trees with the annual crops we already know and grow. They include many agroforestry practices. Carbon sequestration is low at 1-5 tons per hectare. The perennial elements may play support roles like slope stabilization or nitrogen fixation, or may be crops themselves. Some are widely practiced like shea nut parkland in Africa (23 million hectares), farmer-managed natural regeneration in Niger (4.8 million hectares), alley cropping with Paulownia trees in China (3 million hectares), and streuobst mixed fruit trees with annuals in Germany (1 million hectares). Other practices include contour hedgerows, windbreaks, living fences, pasture cropping, and evergreen agriculture.

intercrop at Denis Flores Agroforestry in France. Image Richard Perkins.
Strip intercropped timber poplars at Denis Flores Agroforestry in France. Image Richard Perkins.

Perennial-Livestock Systems

In these systems livestock are integrated with perennials like trees or pasture. Carbon sequestration is mostly low to medium with managed grazing around 2-4 tons per hectare per year, and silvopasture at 1-10. A few case studies have seen sequestration of 36 and even 40 tons per hectare. Generally the more trees, the more carbon. People already consume livestock products like meat, milk, and eggs, so we don’t need to change our diets – instead we let the animals eat the perennials. Ruminants do produce methane which can reduce the impact of carbon sequestration of these systems, though not reverse it. Again some of these are widely practiced, like holistic grazing (12-20 million hectares worldwide), dehesa silvopasture in Spain and Portugal (5.5 million hectares), and Central American silvopasture (9 million hectares). Practices include managed grazing, silvopasture (trees with pastrure), fodder trees and fodder banks, aquaforestry (aquaculture plus trees), and crop-livestock integration.

Alder silvopasture at Las Cañadas in Mexican highlands. Image Ricardo Romero.
Alder silvopasture at Las Cañadas in Mexican highlands. Image Ricardo Romero.

Fully Perennial Systems

These systems sequester the most carbon (medium to very high) but may require the biggest changes to our food system. Coppice and biomass systems can sequester 1-6 tons/hectare/year, with tree crops and bamboo much higher at 2-28 and 6-33 tons/hectare/year respectively. Multistrata agroforestry systems sequester a remarkable 4-40 tons/hectare/year making them the world’s best carbon-sequestering food production model (development of commercial multistrata models for cold climates largely awaits innovative producers and researchers).  Perennial crops are grown on 153 million hectares globally, along with bamboo (22 million hectares), cacao agroforestry systems (7 million hectares), and more. These systems include orchards and plantations, bamboo systems, traditional and short rotation coppice and biomass grasses, multistrata systems like tropical homegardens (food forests) and larger scale multi-layered perennial production systems, and newer systems like woody agriculture and perennial grain production. Perennial staple crops have have a major role to play in a carbon-friendly future but may require big changes in the way we farm and eat.

14.1d loaded chestnut
Chestnuts are already a global perennial staple crop with half a million hectares in production.
Commercial multistrata system featuring alder (for timber, firewood, and nitrogen fixation) over tea (shade crop).
Commercial multistrata system featuring alder (for timber, firewood, and nitrogen fixation) over tea (shade crop). Image World Agroforestry Center.
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Short-rotation coppice mechanized harvest of biomass willow. Image D. Angel, SUNY ESF.

Other Practices

These are mostly non-biological systems that involve design, equipment, or other non-living elements. Carbon sequestration is variable and in some cases (like keyline) unknown. Drip irrigation (which prevents soil salinization and carbon loss in dryland climates) is practiced on 10 million hectares globally, and Amazonian terra preta (biochar plus) includes perhaps a million hectares or more. This set of practices includes rainwater harvesting, keyline, productive restoration, and more.

Keyline farming at Rancho San Ricardo in Oaxaca, Mexico. Image Rodrigo Quiros.
Keyline farming at Rancho San Ricardo in Oaxaca, Mexico. Image Rodrigo Quiros.

These systems need to be combined with perennial crops, new technologies, new markets, citizen movements and policy changes to fully realize the potential of agriculture to sequester up 10-85% of the 200 gigatons needed to get us back down to the magic number of 350ppm.

 

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Legume Trees with Pods Edible by Livestock

This article is an excerpt from my forthcoming book Carbon Farming: A Global Toolkit for Stabilizing the Climate with Tree Crops and Regenerative Agriculture Practices, and is part of a series promoting my kickstarter campaign to raise funds with which to complete the book. You can pre-order a copy and help make it possible for me to get this book out soon.

Joaquin_Sorolla_y_Bastida_-_Algarrobo
This painting by Joaquin Sorolla y Bastida shows sheep enjoying the shade and dropped pods of an ancient carob tree. Courtesy Wikimedia Commons.

Rotational grazing is one the most powerful tools we have to sequester carbon through agriculture. We can increase its carbon-sequestering capacity, and its livestock production power, by adding widely-spaced trees. This practice of integrating trees with grazing is called silvopasture. Studies have shown that in many cases trees actually increase the productivity of pasture beneath them, especially trees that cast light shade.

This article is about a particular kind of silvopasture, where the trees literally drop food to the livestock grazing below. Around the world there are many farming systems that utilize this concept, most famously the dehesa of Spain and Portugal which produces gourmet acorn-fed pork. Here I’m narrowing the focus a bit more, to legume trees that drop nutritious pods to the ground for ruminant livestock like cattle, sheep, and goats. There are “fodder pod trees” like this for most of the world’s climates.

Pods of carob, a tree for Mediterranean climates. Great livestock fodder and edible for humans as well.
Pods of carob (Ceratonia siliqua), an ancient Mediterranean crop. Great livestock fodder and edible for humans as well. Courtesy Wikimedia Commons.

These trees are providing more than just food for animals. Livestock enjoy the shade they provide, especially in the tropical sun. Many of these trees fix nitrogen. Some even have pods edible for humans.

Unfortunately not all of these pods fall to the ground when ripe, some must be knocked off the tree with poles, increasing labor requirements. To my knowledge there has been little or no breeding of these trees for the purpose of feeding livestock. The foliage of many serves as a fodder, and some make excellent firewood as well.

The great majority of these species hail from semi-arid Africa savannahs, but this may in part result from a lack of research in other regions. Surely there are many, many more. Savannahs would be the best place to search for such species as they have coevolved with large grazing and browsing animals. An asterisk (*) indicates pods also edible by humans. Sources: Nitrogen Fixing Tree Association NFT Highlights and World Agroforestry Center Agroforestree Database.

Latin Name Climate Native Range Nitrogen Fixation
Acacia leucophloea semi-arid tropical lowlands Asia yes
Acacia nilotica semi-arid tropical lowlands Africa yes
Acacia saligna semi-arid tropical lowlands Australia yes
Acacia senegal semi-arid tropical lowlands and highlands Africa yes
Acacia seyal arid to semi arid tropical lowlands Africa yes
Acacia tortolis arid to semi-arid tropical lowlands, highlands Africa yes
Adenanthera pavonina semiarid to humid tropical lowlands Asia yes
Cassia grandis humid lowland tropics tropical Americas some
*Ceratonia siliqua Mediterranean Mediterranean no
Enterolobium cyclocarpum     yes
*Erythrina edulis semi-arid to humid tropical highlands Andes yes
*Faidherbia albida arid to humid tropical lowlands and highlands Africa yes
*Gleditsia triacanthos cold humid and arid, Mediterranean, tropical highlands North America no
Newtonia buchananii humid tropical lowlands and highlands Africa no
*Parkia biglobosa semiarid to humid tropical lowlands Africa yes
*Parkinsonia aculeata arid to semiarid tropics and subtropics Americas no
*Piliostigma thongii semiarid tropics Africa yes
Pithecellobium dulce semi-arid to humid tropical lowlands Americas yes
Prosopis africana     yes
*Prosopis alba semi-arid tropics South America yes
Prosopis chilensis semi-arid tropics and subtropics South America yes
Prosopis cineraria arid to semi-arid tropical lowlands Asia & Middle east yes
*Prosopis glandulosa arid to semi-arid, subtropics to cold North America yes
*Prosopis juliflora     yes
*Prosopis pallida semiarid tropics South America yes
Prosopis tamarugo arid tropics South America yes
Samanea (= Albizia) saman semi-arid to humid tropical lowlands tropical Americas yes
Senna singueana semiarid tropics Africa no

Again note that nitrogen-fixing legumes are often likely to escape from cultivation. Always investigate your regional native plant resources first. I’m quite certain that there are tens or hundreds more species that produce fodder pods, as well as many more that drop food of one kind or another to ruminants. For example there are many more species of honey locust (Gleditsia) in Asia.

The pods of Acacia nilotica, from African semi-arid savannahs. Courtesy Wikimedia Commons.
The pods of Acacia nilotica, from African semi-arid savannahs. Courtesy Wikimedia Commons.
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Cassia grandis, from the humid tropical Americas. Courtesy Wikimedia Commons.
Gleditsia_triacanthos_seed_pod
The North American honey locust (Gleditia triacanthos), a good choice for cold temperate climates. Courtesy Wikimedia Commons.
The sweet pods of mesquite (Prosopis glandulosa), a nitrogen-fixing tree for cold, arid landscapes.
The sweet pods of honey mesquite (Prosopis glandulosa), a North America nitrogen-fixing tree for cold, arid landscapes. There are mesquites throughout the dry Americas as well as native species from Africa and Asia, for highlands and lowlands, arid and semi-arid climates. Courtesy Wikimedia Commons.

 

 

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Perennial Cereal Grains: A Promise Requiring Patience and Prioritization

This article is an excerpt from my forthcoming book Carbon Farming: A Global Toolkit for Stabilizing the Climate with Tree Crops and Regenerative Agriculture Practices, and is part of a series promoting my kickstarter campaign to raise funds with which to complete the book. You can pre-order a copy and help make it possible for me to get this book out soon.

Thinopyrum_intermedium_field
Field of ripening intermediate wheatgrass (Thinopyrum intermedium) at The Land Institute’s research farm in Salina, Kansas. Courtesy Wikimedia Commons.

Imagine corn, wheat, or rice that comes back every year without saving seed, tilling, or replanting. Such crops could have a tremendous impact in restoring degraded farmland, rebuilding soil, and sequestering carbon while providing humanity with the staff of life.

The dream of perennial grains is getting tantalizingly closer. Today there is more hopeful news than there was even just a few years ago. In 2009 the First International Perennial Grain Breeding Workshop gathered researchers from all over the world. Land Institute research director Stan Cox proclaimed “we will look back on this workshop as the international launching of the perennial grain revolution.”

Perennial grains include cereals (grass seeds), legumes (dry beans), and oilseeds. In this article I’m focusing just on what’s happening with perennial grass seeds, though in the book I’ll be addressing all three categories and many more.

When compared with other perennial staple crops, perennial cereals have their pros and cons. Their big advantage is that they are basically familiar. People already know how to harvest, process, cook, and eat them. Existing equipment and infrastructure needs few if any changes to handle them. There are perennial cereals under development for almost every climate, from the northern plains to equatorial highlands to salty tropical delta farmland.

Unfortunately perennial grains are still a decade or more in the future, though thanks to the visionary work of the Land Institute and others, we are already decades closer to achieving that goal. There are a number of breeding challenges, whether one seeks to “perennialize” existing annual crops or domesticate wild perennials.

My own attempts to grow perennial grains here in Massachusetts have all failed. Perennial selections of wheat, rye, corn, sorghum, and Agrotriticum were all either winterkilled or proved to be annuals. I will be giving it a try again this year with a perennial wheat from Oikos Tree Crops.

Fast-tracking perennial grain development should be a high priority for use of climate change funds and efforts. They are within our reach, and researchers have a road map to achieving this remarkable goal.  My thanks to the network of NGOs, Universities, governments, and backyard breeders who are making it happen. Funding may be the biggest obstacle between us and long-lived, soil-protecting, climate-stabilizing versions of the familiar crops we depend on today. A primary aim of my forthcoming book is to mobilize much greater support for development of perennial crops and production systems.

F3 seeds from a perennial F2 rice plant (D. Van Tassel, 2009)
F3 seeds from a perennial F2 rice plant (D. Van Tassel, 2009). Courtesy Wikimedia Commons.

MAJOR WORLD CEREALS AND A PROMISING NEW GRAIN

Corn or Maize (Zea mays) is one of the most important staple crops on the planet. Perennial corn could slow or reverse the degradation of sloping lands around the world that are inappropriately used to grow annual maize. Scientists and backyard breeders have been working toward this goal for many years, and have made some limited progress. Diploid perennial teosinte (Z. diploperennis) is a wild relative which is crossable with annual corn. Several other wild corn relatives have recently been found by scientists. Maize can also be crossed with more distantly related hardy perennials including Eastern gammagrass (Tripsacum dactyloides) and the related dwarf Fakahatchee grass (T. floridanum).

The Land Institute has made substantial progress towards developing perennial corn. Their breeders report that with sufficient funding a perennial corn could be ready for field tests in as little as ten years. One challenge is that the perennial rhizomes that overwinter the plants are not cold-hardy, so their breeding is focused on deeper rhizomes that survive below the frost line. Of course this consideration is not important in the tropics where millions of people rely on corn as a staple.

Recently the US Department of Agriculture has begun to show interest in perennial corn breeding. If they were to dedicate a tiny fraction of their budget to this effort, great progress could be made.

First-generation cross of annual corn and diploid perennial teosinte. Photo (and breeding) courtesy Craig Hepworth.
First-generation cross of annual corn and diploid perennial teosinte. Photo (and breeding) courtesy Craig Hepworth.

Nipa (Distichlis palmeri) is a perennial salt-tolerant grass of the Sonoran desert deltas. The flavor of its grain is apparently excellent. Once a staple of the Cocopa people, wild populations of nipa have been greatly reduced due to dams and other watershed disruptions. Wild patches of nipa have been estimated to yield 1.25 tons per hectare, making this one of the most promising perennial grains on the planet. As a C4 grass it is particularly efficient at photosynthesis.

Dr. Richard Felger, a researcher associated with the University of Arizona herbarium and the Sky Island Alliance, has been researching the potential of nipa as a salt-tolerant perennial grain for decades. Though there were some efforts to commercialize the crop too early by other researchers, Felger feels that it will become a major world crop, comparable to short grain rice in grain size and flavor.

Nipa tolerates salty conditions including irrigation with saltwater, and can handle wet conditions. In the wild, the saltmarshes it grows in are inundated twice daily by tidal seawater. It does not, however, require salt or waterlogging. As unsustainable irrigation practices and sea level rise result in increasing salinization of coastal plain farmlands, nipa could become prominent in regions like the Colorado, Ganges, Indus, Murray, and Nile deltas. It is adapted to tropical and subtropical conditions, and prospects for crossing it with the cold-hardy D. spicata are not promising.

Nipa is still undomesticated, and poses several challenges. Roughly half of plants are seedless males. It also appears to take several years after planting until full yields are achieved.

This perennial grain, already a staple for ages, has great promise for salty tropical areas and beyond. Nipa development should be a high priority to agencies and individuals concerned with food security, salinization, and climate change. Perhaps it may also offer an opportunity to develop productive revegetation of barrier islands, to provide protection to coastal areas from extreme weather events.

Rice (Oryza sativa). Rice has several perennial relatives, one an African perennial rice and the other actually a strain of the wild ancestor of annual rice. Under some conditions, some annual rice plants will “rattoon” (re-sprout) for several years. Perennial rice breeding work was carried out at the International Rice Research Institute in the Philippines in the 1990s, and was picked up by the Yunnan Academy of Agricultural Sciences in Kunming, China in 2007. Perennial rice breeding is very challenging and many factors need to be overcome before field testable material is available. The current focus is on replacing annual upland rice, which is grown on steep slopes, as opposed to irrigated paddy rice, which is grown in terraces or level fields. Pest and disease control are challenges in perennial rice as crop rotation is not an option.

The Land Institute reports that Yunnan Academy breeder Hu Fengyi has lines of rice that have produced grain for three years in a row, with yields competitive with annual rice. This is very promising news, as the prospect of perennial rice could have tremendous impact in tropical and subtropical areas of the world.

Rice_research_plots
Research plots in a perennial rice breeding nursery belonging to the Yunnan Academy of Agricultural Sciences near Sanya, Hainan Province, PRC. Courtesy Wikimedia Commons.

Rye (Secale cereale) is one of the perennial cereals that is closest to commercial viability. Annual rye has been crossed with a wild rye (S. montanum) and several varieties have been developed, including “Permontra” and “ACE-1”. In a recent study perennial ryes yielded 73% as well as their annual counterparts in years one and two. Not enough plants came back for a third year to make further measurement possible. Annual rye itself yields quite a bit lower than annual wheat. Nonetheless, we are probably closer to seeing perennial rye in production on real farms than most other global cereals.

Sorghum (Sorghum bicolor) is weakly perennial in the tropics and “rattoons” or re-sprouts for several years in ideal conditions. Perennial sorghum breeding at the Land Institute has focused on crosses with the perennial weed Johnsongrass (S. halipense). Like corn, there are challenges in overwintering tender rhizomes, which would not be an issue in the tropics. Perennial sorghum is farther along than most of the other perennial versions of major grains but is not yet ready for prime time. Perennial sorghum could be bred not just for grain but also for sweet syrup, which was once made from the stalks across the American Midwest. Sorghum is very versatile in terms of climates to which it is suited, but it is particularly appropriate to dry regions where it can outperform corn.

Sorghum2
Perennial sorghum breeding nursery at The Land Institute. Courtesy Wikimedia Commons.

Wheat (Triticum aestivum). Perennial wheat breeding efforts began in the Soviet Union almost one hundred years ago. Only with recently developed techniques is perennial wheat breeding beginning to show results. Perennial wheats are typically crossed with wheatgrass (Thinopyron) species.

Several universities are working alongside the Land Institute on perennial wheat breeding including Washington State. In one Washington State study, some perennial wheat varieties yielded 93% as well as annual wheat the first year – most impressive. In a more recent study, perennial forms yielded 50% as well as annuals, in both the first and second years. Most of the plants died after their second harvest.

The Land Institute has had no success in perennial wheat survival in Kanasas (nor have I in Massachusetts). An Australian economic study has shown that perennial wheats could be economically viable if they yielded just 40% as well as annual wheat, but provided good fodder for several years after for grazing sheep. It seems that even this relatively low bar has not yet been cleared by perennial wheat, but breeding work continues.

Hybrid_perennial_wheat_in_the_field
Heads of plant derived from hybridizing wheat with Thinopyrum intermedium. These plants are completely male sterile, but they are strong perennials. Courtesy Wikimedia Commons.

Additional Perennial Grains Worth Exploring

Barley (Hordeum vulgare) is adapted to very cold and short-season environments. The annual form has been crossed with a wild perennial (H. jubatum), probably to impart improved vigor or disease resistance. Researchers in Scandinavia, northern Canada, and Siberia might turn their attention to the potential of perennial barley for their regions.

Indian Ricegrass. This perennial North American native (Oryzopsis hymenoides) was a major staple to indigenous peoples of the west. Discovery of a non-shattering clone allows it to be grown today on a commercial scale in Montana, producing a specialty gluten-free flour marketed as “Montina”. High prices make up for low yields, and about 3,000 acres are in production. Little breeding work has been done of this remarkably drought- and cold-tolerant perennial grain.

Indian ricegrass is a candidate perennial grain for cold, arid climates.
Indian ricegrass is a candidate perennial grain for cold, arid climates.

Intermediate Wheatgrass (Thinopyrum intermedium). The Land Institute has been working for several decades to domesticate this perennial wild grain. They have had relatively rapid success, and intermediate wheatgrass is currently undergoing a 30-acre field trial. The research fields are burned annually to control weeds, and apparently the crop can also be grazed to provide a non-seed yield. Production is still low, though researchers aim to see it reach one ton per acre. Thinopyrum species are also used as the perennial parent in attempts to develop perennial wheat.

Job’s Tears (Coix lacryma-jobi). Wild Job’s tears is a perennial from South and Southeast Asia. The seeds of the wild forms (var. stenocarpa and var. monilifer) have thick, hard shells that are often used as beads. These forms are grown around the world as ornamentals, and have naturalized widely. Though they have edible seeds, the shells make these forms impractical for use as food. Farmers in India domesticated an annual or mostly annual form with thin, soft shells (var. ma-yuen) between 3-4,000 years ago, which by 2,000 years ago was being grown in China. Before the arrival of corn, Job’s tears was an important grain in subtropical Asian highlands. Annual Job’s tears yields a respectable 2-3.5 tons per acre, and tolerates acid, poor, and waterlogged soils. Crossing annual grain types with perennial forms could result in a new perennial grain for the tropics and subtropics, including highland areas.

Job's tears. This is the perennial, less edible variety.
Job’s tears. This is the perennial, less edible variety grown as an ornamental.

Markouba Grass, or Afezu (Panicum turgidum) is a wild perennial grass, ranging from the heart of the Sahara desert through Pakistan. It grows in areas with as little as 25mm (1”) of precipitation, spreading by stolons to stabilize sand dunes. Markouba grains are an important staple in the Sahara. Efforts at domesticating this species could serve the dual functions of feeding people in very arid tropical areas and reversing desertification. It might be crossed with proso millet (P. miliaceum), an important annual world grain.

Oats (Avena sativa) are important both as livestock fodder and in oatmeal breakfasts in cold climates around the world. Oats have been hybridized with the perennial A. macrostachya, though not for the purpose of creating perennial oats. Who will rise to this challenge?

Pearl Millet (Pennisetum glaucum) is an important world grain, thriving in arid environments and poor soils. It has been crossed with the (very weedy) perennial elephant grass P. purpureum. A perennial millet could be significant in Africa and India where millions of people rely on millet for survival.

Woollybutt Grass (Eragrostis eriopoda) is an Australian wild edible that has served as an important staple to indigenous people there for millennia. They are reported to have been the most important native grass seed, in part because of the ease of processing seeds, high yields, and holding on the plant for months. This species is now cultivated on a small scale by “bush tucker” (wild edibles) enthusiasts in Australia.

References and Further Reading

Cox et al. “Prospects for developing perennial grain crops” in Bioscience, 56: 649-659 (2006).

Duke, James. Handbook of Energy Crops, unpublished 1983, online at http://www.hort.purdue.edu/newcrop/duke_energy/dukeindex.html, accessed April 16 2013.

Glover et al. “Increased food and ecosystem security via perennial grains” in Science 328: 1638-1639 (2010).

Hayes, R.C. et al. “Perennial cereal crops: An initial evaluation of wheat derivatives”, in Field Crops Research 133: 68-89 (2012).

Jaikumar et al. “Agronomic assessment of perennial wheat and perennial rye as cereal crops” in Agronomy Journal, 104:1716-1726 (2012).

Low, Tim. Wild Food Plants of Australia, Angus & Robertson, 1991.

O’Barr, Scott. Alternative Crops for Drylands. Amaigabe Press, 2013.

National Research Council. Lost Crops of Africa Vol. I: Grains. National Academy Press, 1996.

Pearlstein, Felger et al… “Nipa (Distichlis palmeri): A perennial grain crop for saltwater irrigation” Journal of Arid Environmental 82 (2012) 60-70

Shim, Junghyun. “Perennial rice: Improving rice production for a sustainable upland ecosystem” in SABRAO Journal of Breeding and Genetics ,44 (2) 191-201, 2012.

Smith, Keith & Irene. Grow Your Own Bushfoods, New Holland Publishers, 1999.

Van den Bergh, M.H. & N. Iamsupasit, 1996. Coix lacryma-jobi L.[Internet] Record from Proseabase. Grubben, G.J.H. & Partohardjono, S. (Editors).
PROSEA (Plant Resources of South-East Asia) Foundation, Bogor, Indonesia. http://www.proseanet.org. Accessed from Internet: 16-Apr-2013

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Siberian Pea Shrub – a Potential Perennial Bean for Cold and Arid Regions

This article is an excerpt from my forthcoming book Carbon Farming: A Global Toolkit for Stabilizing the Climate with Tree Crops and Regenerative Agriculture Practices, and is part of a series promoting my kickstarter campaign to raise funds with which to complete the book.

Siberian Pea Shrub (Caragana arborescens). This shrub from Siberia and other semiarid parts of Northeastern Asia is remarkably cold hardy – tolerating temperatures below -40, the frigid temperature where Celsius and Fahrenheit overlap. It is widely used for windbreak, nitrogen fixation, livestock fodder, and erosion control in the world’s cold regions. It is particularly common in the Canadian prairies, where hundreds of miles of pea shrub windbreaks have been planted.

Siberian pea shrub produces fairly high yields of small beans. Canadian farmers use the beans as survival food, boiling them in several changes of water in lean years to remove the bitterness. That doesn’t quite meet my definition of edible. However, Facciola’s Cornucopia: A Source Book of Edible Plants reports the dry beans contain up to 36% protein – very similar to soybeans.

Siberian pea shrub loaded with beans at Central Rocky Mountain Permaculture Institute.
Siberian pea shrub loaded with beans at Central Rocky Mountain Permaculture Institute.

Somewhere out there in the wilds of Siberia or in a lonely windbreak in Saskatchewan, the perfect edible pea shrub may very well already exist. This crop offers the potential for a long-lived woody protein crop for the world’s boreal forests and grasslands, semi-arid mountains, and other inhospitable climates. Screening existing populations for edibility, and breeding lines of truly edible pea shrubs should be a high priority for researchers in cold and arid climates, including backyard and amateur breeders. Breeding techniques were worked out in the 1960s in Canada for shelterbelt purposes (Cram, E.H. “Breeding and Genetics of Caragana”, The Forestry Chronicle, p. 400-401 (1969)), which gives us a head start. This species has naturalized in some parts of the US and Canada.