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A revolution for our soil March 22nd, 2020 by

la versión en español a continuación

Degraded soil can be repaired, and replenished with nutrients, until it produces abundant harvests at lower costs, while removing carbon from the atmosphere, and putting it back into the ground. This is the optimistic message of David Montgomery’s book, Growing a Revolution.

In many parts of the world, soils have been degraded by frequent plowing. The benefits of releasing a burst of nutrients for the crops and killing weeds are overcome by exposure of the soil to erosion by wind and water (see Out of space on Montgomery’s earlier book Dirt: The Erosion of Civilizations). In the Midwestern USA perhaps half of the original prairie soil, and most of its organic matter, have been lost in little more than a century of conventional tillage. Chemical fertilizers provide the major nutrients of phosphorous, potassium and nitrogen in the short run, but they undermine the soil’s long-term health by suppressing mycorrhizal fungi.

These mycorrhizal fungi feed plants while making glomalin, a protein that binds soil particles together. Plowing destroys the soil structure created by beneficial fungi and their glomalin.

Montgomery, a professional geologist, explains that most soils don’t need chemical fertilizer. They have enough phosphorous, potassium and all the minor nutrients like iron and zinc that plants need, but these minerals are locked up in stone particles and other forms not accessible to the plants. The key to using these nutrients are beneficial microbes, like the mycorrhizal fungi that extract mineral nutrients from rock fragments and help to break down organic matter so plants can use it. Microbes trade phosphorous to plants for sugars. Predatory arthropods, nematodes and protozoa then feast on the microbes and release the nutrients back to the soil. A diverse soil life makes soil more fertile. Synthetic fertilizers interrupt these interactions, and the mycorrhizal fungi die, so the crop becomes chemical-dependent. Soil that is rich in organic matter (that is, in carbon) is healthier and supports a thriving community of beneficial microorganisms.

But with proper care, soil can be brought back to good health in just a few years. The right techniques can boost soil carbon from 1% (typical of degraded soils) to 4% (as in undisturbed forest) or even up to 6%. There are many such techniques and they go by various names, including “conservation agriculture,” “agroecology” or “regenerative agriculture,” and they are based on simple principles: 1) Use cover crops (or mulch) to keep the soil covered all the time; 2) Complex crop rotations of grasses, legumes and other crops; and 3) no-till, planting seeds directly into the unplowed earth.

Montgomery takes his readers to meet farmers from Kansas to Pennsylvania, from Ghana to Costa Rica, who are practicing and profiting from these three principles. Some are organic farmers; others apply small amounts of nitrogen fertilizer directly into the soil, near the seed, where the plant can efficiently take it up. We learn that some use earthworms, while others like Felicia Echeverría in Costa Rica make their own brews of beneficial microorganisms, to add life to dead soil. Gabe Brown in North Dakota rotates cattle in small paddocks, on large fields. As the cows graze, they fertilize the soil with manure.

Montgomery and soil scientist Rattan Lal estimate that conservation agriculture could offset a third to two thirds of current carbon emissions, by putting organic matter back into the soil, while tilling less and so lowering fuel expenses. Stumbling blocks to adoption of conservation agriculture include subsidies and crop insurance that keep farmers plowing and dependent on chemical fertilizer. Another is formal research, which continues to favor studies of products that companies can sell: chemical solutions to biological problems, as Montgomery puts it. Only 2% of US agricultural research goes to regenerative agriculture (and only 1% globally). Much of the innovation to revive the soil is driven not by funded research, but by the farmers themselves, who have shown that conservation agriculture, agroecology and permaculture can be more productive, with fewer pest problems. Conservation agriculture saves on expenses for inputs, so it is more profitable than conventional tillage agriculture. Properly conserved soil has little erosion; it soaks up the rain in wet years and holds the moisture for drought years.

Montgomery is concerned that when large-scale, industrialized farmers convert from tillage to conservation agriculture there must be a transition period when profits sag, before the soil improves enough to bring yield back up. He fears that this can discourage farmers from switching to conservation agriculture. Yet I am sure that the farmers themselves will work this out. As the natural experimenters that they are, farmers can try ecological farming practices with reduced tillage, first on one field, or on part of one, gradually creating the practices they need, one plot at a time. The good news is that conservation agriculture can be adopted on large farms or small ones, conventional or organic, mechanized or not. Farming can rebuild the soil, and does not need to destroy it.

Further reading

Montgomery, David R. 2017 Growing a Revolution: Bringing Our Soils Back to Life. New York: Norton. 316 pp.

Related blog stories

Encouraging microorganisms that improve the soil

Effective micro-organisms

Farming with trees

Out of space

The big mucuna

From uniformity to diversity

Related videos

Good microbes for plants and soil

Mulch for a better soil and crop

Reviving soils with mucuna (how to use a popular cover crop, mucuna, or velvet bean)

Intercropping maize with pigeon peas

Making a vermicompost bed

The wonder of earthworms (rearing earthworms to fertilize fields and gardens)

Animals & trees for a better crop

SLM00 Introduction (an introduction to a series of 12 videos on conservation agriculture)

Grow more, earn more (small machinery to reduce tillage)

Till less to harvest more (no-till and minimum tillage)

And many other videos on www.accessagriculture.org

UNA REVOLUCIÓN PARA NUESTRO SUELO

Por Jeff Bentley, 22 de marzo del 2020

El suelo degradado puede ser reparado, devolviendo sus nutrientes, hasta que produzca cosechas abundantes a costos más bajos, mientras que se saca carbono de la atmósfera, para ponerlo en el suelo. Este es el mensaje optimista del libro de David Montgomery, Growing a Revolution.

En muchas partes del mundo, el arar frecuentemente ha degradado los suelos. El arado trae los beneficios de liberar nutrientes repentinamente para los cultivos y matar las malezas, pero el daño es mayor debido al exponer el suelo a la erosión del viento y del agua (ver Out of space sobre el libro anterior de Montgomery, Dirt: The Erosion of Civilizations). En el Medio Oeste de los Estados Unidos, quizás la mitad del suelo original de la pradera, y la mayor parte de su materia orgánica, se han perdido en poco más de un siglo de labranza convencional. Los fertilizantes químicos proporcionan los principales nutrientes de fósforo, potasio y nitrógeno a corto plazo, pero socavan la salud del suelo a largo plazo al suprimir los hongos micorriza.

Estos hongos micorriza alimentan a las plantas mientras fabrican glomalina, una proteína que une las partículas del suelo. El arado destruye la estructura del suelo creada por los hongos benéficos y su glomalina.

Montgomery, un geólogo profesional, explica que la mayoría de los suelos no necesitan fertilizantes químicos. Tienen suficiente fósforo, potasio y todos los nutrientes menores como el hierro y el zinc que las plantas necesitan, pero estos minerales están encerrados en partículas de piedra y están en otras formas no accesibles para las plantas. La clave para el uso de estos nutrientes son los microbios buenos, como las micorrizas que extraen nutrientes minerales de los fragmentos de roca y ayudan a descomponer la materia orgánica para que las plantas puedan usarla. Los microbios intercambian fósforo a las plantas por azúcares. Los artrópodos, nematodos y protozoos depredadores comen los microbios y liberan los nutrientes de vuelta al suelo. Una vida diversa en el suelo lo hace más fértil. Los fertilizantes sintéticos interrumpen estas interacciones y las micorrizas mueren, por lo que el cultivo se vuelve químicamente dependiente. El suelo rico en materia orgánica (es decir, en carbono) es más saludable y sostiene una próspera comunidad de microorganismos buenos.

Pero con el cuidado adecuado, el suelo puede volver a tener buena salud en pocos años. Las técnicas correctas pueden aumentar el carbono del suelo del 1% (típico de los suelos degradados) al 4% (como en los bosques vírgenes) o incluso hasta el 6%. Existen muchas de esas técnicas y tiene diversos nombres, como “agricultura de conservación”, “agroecología” o “agricultura regenerativa”, y se basan en principios sencillos: 1) Sembrar cultivos de cobertura (o mulch) para mantener el suelo cubierto todo el tiempo; 2) rotaciones complejas de cultivos de pastos y cereales, leguminosas y otros cultivos; y 3) la labranza cero, sembrando las semillas directamente en la tierra sin arar.

Montgomery lleva a sus lectores a conocer a agricultores de Kansas a Pensilvania, de Ghana a Costa Rica, que practican rentablemente estos tres principios. Algunos son agricultores orgánicos; otros aplican pequeñas cantidades de fertilizante de nitrógeno directamente en el suelo, cerca de la semilla, donde la planta puede absorberlo eficazmente. Aprendemos que algunos usan lombrices de tierra, mientras que otros, como Felicia Echeverría en Costa Rica, elaboran sus propias soluciones de microorganismos benéficos, para dar vida al suelo muerto. Gabe Brown, en Dakota del Norte, rota el ganado en pequeños potreros, en grandes campos. Cuando las vacas pastan, fertilizan el suelo con estiércol.

Montgomery y el científico del suelo Rattan Lal estiman que la agricultura de conservación podría compensar entre un tercio y dos tercios de las actuales emisiones de carbono, devolviendo la materia orgánica al suelo, a la vez que se labra menos y se reducen así los gastos de combustible. Entre los obstáculos para la adopción de la agricultura de conservación hay los subsidios y los seguros de los cultivos que mantienen a los agricultores arando y dependiendo de los fertilizantes químicos. Otro es la investigación formal, que sigue favoreciendo los estudios de productos que las empresas venden: soluciones químicas a problemas biológicos, como dice Montgomery. Sólo el 2% de la investigación agrícola estadounidense se destina a la agricultura regenerativa (y sólo el 1% a nivel mundial). Gran parte de la innovación para revivir el suelo no está impulsada por la investigación académica, sino por los propios agricultores, que han demostrado que la agricultura de conservación, la agroecología y la permacultura pueden ser más productivas, con menos problemas de plagas. La agricultura de conservación ahorra gastos en insumos, por lo que es más rentable que la agricultura de labranza convencional. El suelo conservado adecuadamente tiene poca erosión; absorbe la lluvia en los años húmedos y retiene la humedad en los años secos.

A Montgomery le preocupa que cuando los grandes agricultores industrializados pasen de la agricultura de labranza a la de conservación, debe haber un período de transición no rentable, antes de que el suelo mejore lo suficiente como para que vuelva a rendir bien. El teme que esto pueda desalentar a los agricultores a cambiar a la agricultura de conservación. Sin embargo, estoy seguro de que los propios agricultores lo solucionarán. Como experimentadores naturales que son, los agricultores pueden probar prácticas de agricultura ecológica con labranza reducida, primero en una parcela, o en un rincón, creando gradualmente las prácticas que necesitan, una parcela a la vez. La buena noticia es que la agricultura de conservación puede adoptarse en fincas grandes o pequeñas, convencionales u orgánicas, mecanizadas o no. La agricultura puede reconstruir el suelo, en vez de destruirlo.

Leer más

Montgomery, David R. 2017 Growing a Revolution: Bringing Our Soils Back to Life. New York: Norton. 316 pp.

Blogs previos sobre temas parecidos

Fomentando microorganismos que mejoran el suelo

Effective micro-organisms

La agricultura con árboles

Out of space

The big mucuna

From uniformity to diversity

Videos sobre el tema

Buenosmicrobios para plantas y suelo

El mulch mejora el suelo y la cosecha

Revivir el suelo con la mucuna (cómo usar un popular cultivo de cobertura, la mucuna, o el frijol terciopelo)

Intercropping maize with pigeon peas

Haciendo una lombricompostera

La maravillosa lombriz de tierra  (criar lombrices de tierra para fertilizar huertos y cultivo)

Animales, árboles y cultivos

SLM00 Introducción (una introducción a una serie de 12 videos sobre la agricultura de conservación)

Producir más, ganar más (maquinaria pequeña para la labranza mínima)

Arar menos para cosechar más (cero labranza y labranza mínima)

Además de muchos otros videos en https://www.accessagriculture.org/es

Toads for watermelon October 13th, 2019 by

The south coast of Jamaica is just right for growing watermelon, where I recently saw the fruit stacked under the shade trees in front of comfortable farm houses. Farmers can earn a tidy living from selling melons on the local market and to the hotels and resorts.

But the trick is to get enough water. In the dry season, a tanker truck will deliver 1000 gallons (almost 4,000 liters) for $50. Most of the farmers economize on water by using drip irrigation. For many years, farmers have saved on water by using mulch, made from the light-weight Guinea grass.

Professional crews cut and dry the grass, which is grown in small fields scattered among the patches of watermelon.  The grass crews lay out a neat carpet of mulch, which not only keeps the soil moist, but also suppresses weeds, and creates a soft, clean bed for the fruit to grow, so it develops an attractive, green rind all the way around the fruit. After harvest, the grass decomposes, enriching the soil with organic matter.

I learned about this while visiting Jamaican farmer Junior Dyer, with a group of colleagues. We asked when Junior watered his plants. He said at 9 or 10 AM. “I never water at night,” Junior explained, because if he does that frogs and toads come into the field to eat the insect pests, but then the amphibians stay for the night, digging holes into the moist soil and disturbing the roots. The frogs and toads still come and eat the insect pests when watering is done in the morning, but then they bed down on the edge of the field.

Junior also showed me some of his 13 beehives, which he moves around to pollinate his melons, cantaloupe and cucumbers. I asked Junior if he used insecticides to control major insect pests such as whiteflies, thrips and especially aphids, which transmit disease (like watermelon mosaic virus). He admitted, a bit reluctantly, that he did use insecticides. I asked how he managed that without killing his bees. Junior replied that he looks for insecticide labelled as bee-friendly. In truth, insecticides are never good for bees, but some are less toxic than others.

Junior’s extension agent, Jermaine Wilson, said that Junior belongs to a farmers’ group, but that the farmers had already observed on their own that toads and frogs are beneficial creatures. Farmers see them eating insects. Beneficial amphibians are an example of how valuable local knowledge often develops around a topic that is culturally important (like watermelon pests) and easy to observe (like toads eating bugs). I found it encouraging that Junior appreciated the frogs and toads, even though they tend to eat larger insects rather than the really small ones that are the main pests in Jamaican watermelon.

I admired the efficient system the Jamaicans have for producing watermelon, even though they still largely rely on insecticides, with little organic production. But the Jamaican farmers are moving in the right direction by encouraging frogs and toads, and beekeeping will certainly motivate them to further reduce insecticides. Watermelons are a fairly sustainable, commercial crop from family farms. The bees pollinate the melon flowers, and the fruit grows nestled in a bed of mulch, precision-watered with drip irrigation. It’s a nice blend of appropriate technology and local knowledge, with frogs and toads contributing along the way.

Acknowledgements

RADA (Rural Agricultural Development Authority) graciously hosted my visit to Saint Elizabeth Parish, Jamaica, as part of the 10th Annual Meeting of GFRAS (Global Forum for Rural Advisory Services).

Related blog stories

Spanish mulch

Drip irrigation saves water in South Sudan

To drip or not to drip

Why drip irrigation isn’t sinking in

Related video

Drip irrigation for tomato

Gauchos for hire October 6th, 2019 by

Picture a gaucho astride a horse on a homemade saddle, galloping like a centaur across the limitless plains of Argentina. Above his broad brimmed hat, he twirls three balls (bolas) tethered together, to fling at the feet of a fleeing bull. The rawhide cords of the bolas wrap around the lower legs of the bull and bring it crashing to the ground.

The gauchos are often portrayed as a romantic even mythical figure, so it is easy to forget that they were workers in commercial agriculture, supplying the world’s markets with export beef, even in the early nineteenth century.

Argentine historian Ricardo Salvatore has written a book about the final, glory days of the gauchos (1829 to 1852), when Argentina was governed by Juan Manuel de Rosas. Now largely vilified in his home country as a dictator and populist, Rosas liberalized markets and freed them from the restrictions and high prices imposed under colonial rule. He awarded government contracts in public, on the steps of the police station, to those who submitted the lowest tender. Rosas insisted that the courts give equal legal treatment to rich and poor, black and white. He created a large army and filled it with rural men, but he also fed their widows and families with beef confiscated from enemy ranchers.

The Argentine civil wars dragged on for decades. Rosas and his party, the Federales, favored less government. They would eventually lose to the rebel Unitarios, who wanted a strong central administration. During the war many rural people, paisanos, migrated to the relative calm of the province of Buenos Aires. Along the way young men were arrested on charges of deserting the army. Fragments of their defense statements, transcribed by court clerks, make up most of the source material for Salvatore’s book.

The gauchos were, by Salvatore’s definition, illiterate. They also worked as ranch and farm hands, and led a simple life. They owned little more than some simple horse-riding tack and the clothes on their back: a shirt, jacket, poncho, home-made boots and a chiripá (a woven cloth worn around the waist, and tucked between the legs).

The vast pampas may have been unfenced but they were policed by small town judges (jueces de paz), and owned by ranchers, who employed the gauchos to raise cattle, and to grow a few crops. Products like dried beef, hides and tallow were carted to Buenos Aires and exported, mainly to Europe. Live cattle were herded to the city. On one single day, 27 February 1847, a whopping 19,073 animals were slaughtered. It’s not clear if this was a routine toll or just a bad day for cows. In those days the meat was salted and exported, before the invention of tinned food and refrigerated shipping.

During the long, violent wars of independence from Spain (about 1809 to 1825), all of the mainland Spanish-American countries, from Mexico to Argentina, emerged as self-governing republics. In Argentina, the struggle for independence had fostered an ideology of equality, which the gauchos held onto during the civil wars that broke out soon after independence was granted. Labor shortages also strengthened the gaucho’s position with their employers. Some would demand advance pay and then vanish. Others insisted on being paid daily, to earn more than the monthly salaries that ranch owners preferred. Employers also lured the gauchos into jobs with rations of beef, tobacco, and sugar. But money and rations weren’t enough to keep gauchos on the job. They insisted on being addressed respectfully. A foreman who barked out orders like a rude command could be challenged to a knife duel by a weather-worn gaucho.

In the mid 1800s, the Argentine ranch owners purposefully played down differences in social status. The ranchers wore the same clothes as their workers, ate almost nothing but meat, and lived in houses where the only furniture was a saddle hanging on the wall.

After the Argentine civil wars ended, Salvatore says that the gauchos faded from history. Deserters were no longer of interest to the small-town judges. And the distinction between Federal and Unitario was less important, so rural travelers stopped being arrested and questioned. Gauchos appear infrequently in the police records, now mostly described as “vagabonds.”

After the 1860s, the beef economy rapidly modernized, with the introduction of barbed-wire fences and railroads. Scottish, Irish and English migrants took over many of the gaucho’s jobs in the countryside. Italians worked in the city in commerce and in packing plants.

The gauchos migrated to the towns and to the frontiers and eventually intermarried with the newcomers. The gauchos were no longer a distinct social group by the end of the 19th century. Gone but not forgotten. Modern Argentina still has an egalitarian touch; even the waiters approach their customers tall and proud, addressing their customers like friends.  Perhaps the tough, friendly spirit of the gauchos lives on, at least a bit.

Further reading

Although Salvatore is Argentine, he wrote in English. Mateo García Haymes and Luisa Fernanda Lassaque’s Spanish translation is so cleverly done that it reads as though it had been written in Spanish.

Salvatore, Ricardo D. 2018 Paisanos Itinerantes: Orden Estatal y Experiencia Subalterna en Buenos Aires durante la Era de Rosas. Buenos Aires: Prometeo Libros.

Original version:

Salvatore, Ricardo D. 2003 Wandering Paysanos: State Order and Subaltern Experience in Buenos Aires Province during the Rosas Era. Durham, North Carolina: Duke University Press.

Spanish mulch September 22nd, 2019 by

Linguists will tell you that each language arranges the world differently. No two languages classify objects, activities or emotions in the same way. This is especially true of the words used in farming.

I was reminded of this recently when translating a video script from English to Spanish. The video, from northern India, forced me to grapple with “mulch”, an English word that is also widely used in Spanish, in real life and on the Internet.  Yet the world’s authority on the Spanish language, the Real Academia Española, does not include “mulch” in its magnificent dictionary, the Diccionario de la Real Academia de la Lengua Española.

It is odd that “mulch” is a new word in Spanish, when it is an old word in English. The Oxford English Dictionary defines mulch as a “Partly rotted plant material, etc.; (Horticulture) loose material consisting of straw, decaying leaves, shredded cuttings and bark etc., spread on soil or around or over a plant to provide insulation, protect from desiccation and deter weeds.” “Mulch” comes from a Middle English word, “molsh” or “mulsh” and has been in the language at least since 1440, and possibly much earlier.

I had my doubt about using “mulch” in Spanish. Various on-line dictionaries suggest “mantillo”, literally “little blanket” instead. But a web search of mantillo usually shows commercial bags of chipped bark used for landscaping and suppressing weeds. Not quite the same as the straw, leaves and husks that farmers have on hand.

I wrote to three agronomists I respect, native Spanish speakers who work closely with farmers. They confirmed that “mulch” was the word to use in Spanish. But one offered a little twist: if the video from northern India was being translated into Quechua, we could say “sach’a wanu.” Now there is a term to savor. “Wanu” means dropping, and is the source of the English word “guano,” meaning bird dung. In Quechua, “wallp’a wanu” is chicken dung, “llama wanu” is llama dung, and “sach’a wanu” is forest mulch, or the fallen leaves of trees.

I was back where I started. So, I decided to use “mulch” in the script, although at the first mention I did offer the alternative “mantillo.”

While languages describe the world in different ways, they also level those differences as they aggressively borrow words from each other, for example “silo”, “lasso”, and “stevedore.” These are all recent loanwords from Spanish to English. New words take time to be defined in dictionaries, which cautiously avoid including fad words that may fade away before really entering the language. But one day “mulch” will be included in the Diccionario de la Real Academia, joining “whisky,” “sandwich,” and other recent English loan words that have enriched the Spanish language.

Watch the video

Mulch for a better soil and crop

What counts in agroecology August 18th, 2019 by

Vea la versión en español a continuación

Measuring the costs and benefits of a small farm can be harder than on a large one, especially if the small farm includes an orchard and makes many of its own inputs, as I saw on a recent visit to Sipe Sipe, near Cochabamba, Bolivia, where a faith-based organization, Agroecología y Fe (Agroecology and Faith) is setting up ecological orchards.

The director of Agroecology and Faith, Germán Vargas, explained that a forest creates soil, gradually building up rich, black earth under the trees, while agriculture usually exposes the soil to erosion. A farm based on trees, with organic fertilizer, and with vegetables growing beneath the trees, should be a way to make a profit while conserving the soil. 

Extensionist Marcelina Alarcón showed us the apple trees that she and local farmers planted in August, 2018. They started by terracing the one hectare of gently sloping land. In one week of hard work they built a 200,000 liter, circular water reservoir of stone and concrete (gravity-fed with stream water) to irrigate the terraces and three additional hectares. The cost was 64,000 Bs. ($9,275), which seems like a big investment, but similar reservoirs built 30 years ago are still working.

Lush beds of lettuce, cabbage, broccoli, wheat, onions (some plants grown for their seed) are thriving beneath the apple trees. When one crop is harvested another takes its place, in complex rotations over small spaces. No chemicals are used, but the group makes calcium sulphate spray and liquid organic fertilizers to improve the soil, prevent crop diseases and enhance the production and quality of the apples and vegetables.

The group has harvested vegetables four times and sold them directly to consumers at fairs organized by Agroecology and Faith for a total gross receipt of 4,380 Bolivianos ($635).

I was visiting the farm at Sipe Sipe with a small group organized by Agroecology and Faith and some of their allies. Some of the lettuce, onions and tomatoes from the farm end up in a tub during our visit, to make a salad for the visitors—part of a fabulous lunch (complete with fresh potatoes and mutton cooked underground) offered at a modest cost. Produce cooked on site and sold informally on the farm are probably not counted when estimating profitability. After the tour of the farm and before the lunch, Marcelina set up a table with some vegetables for sale. She was kept quite busy writing down each transaction as we bought small bags of tomatoes and other produce for amounts less than a dollar each.

The sale of half a kilo of tomatoes is as much work to document as the sale of twenty tons of rice. A small farm has many more sales than a large farm and it takes a lot of administrative work to keep track of produce that is not sold because it goes into seed, feed or onto the family table.

The cost:benefit of a conventional field is simpler to tabulate: so much labor, machinery, seed and chemicals, all purchased, and single crop yields measured with relative ease. Yet this doesn’t tell the whole story. Loss of soil due to erosion, or carbon and nitrogen to the atmosphere, or pollution from fertilizer run-off all have a cost, even if they are often dismissed as “externalities.”

An agroforestry system like the hectare of apples and vegetables we visited starts with a large investment in irrigation and terracing. Many of the inputs are labor, or home-made fertilizers, and their cost is not always counted. The apple trees have not yet borne fruit, and some of the vegetables may escape the bookkeeper’s tally. Yet here the “externalities” have a positive and valuable contribution: soil is being created, chemical pollution is nil, and livelihoods are enriched as local farmers, mostly women, learn to work together to produce healthy food to sell. Classical economic comparisons with conventional farms fail to take account of these benefits.

Even a small farm can have a lot to consider in estimating returns, with many crops and activities and environmental services. Until we learn to measure the environmental efficiency as well as financial profitability of agroforestry or agroecological farms properly, they will never look as good as they really are.

Further reading

A recent report from the FAO (the UN’s Food and Agriculture Organization) concludes that yield data is too poor a parameter to compare conventional (over-plowed, chemical intensive) agriculture with agroecology, a beyond-organic agriculture with soil conservation and respect for local communities.

HLPE Report on Agroecological and other innovative approaches for sustainable agriculture and food systems that enhance food security and nutrition. Extract from the Report: Summary and Recommendations (19 June 2019). Rome: FAO http://www.csm4cfs.org/summary-recommendations-hlpe-report-agroecology-innovations/

Related blogs

Out of space

Enlightened agroecology

Apple futures

Gardening against all odds

LO QUE CUENTA EN LA AGROECOLOGÍA

Por Jeff Bentley, 18 de agosto del 2019

Medir los costos y los beneficios de una pequeña finca puede ser más difícil que en una grande, especialmente si la pequeña incluye árboles y produce muchos de sus propios insumos, como vi en una reciente visita a Sipe Sipe, cerca de Cochabamba, Bolivia, donde la organización eclesial “Asociación Agroecología y Fe” (AAF) está estableciendo huertos ecológicos agroforestales.

El director de la AAF, Germán Vargas, explicó que un bosque crea suelo, acumulando gradualmente tierra negra y rica bajo los árboles, mientras que la agricultura suele exponer el suelo a la erosión. Una finca basada en árboles, con abonos orgánicos, y con hortalizas que crecen debajo de los árboles, debería ser una forma de obtener beneficios al mismo tiempo que se conserva el suelo. 

La extensionista Marcelina Alarcón nos mostró los manzanos que ella y la gente local plantaron en agosto del 2018. Comenzaron haciendo terrazas en una hectárea en suave pendiente. En una semana de trabajo duro construyeron un reservorio circular de agua de 200.000 litros de piedra y concreto (llenado por gravedad de agua de riachuelo) para regar las terrazas y tres hectáreas adicionales. El costo fue de 64.000 Bs. ($9,275), que parece una inversión grande, pero reservorios similares construidos hace 30 años siguen funcionando.

Camellones exuberantes de lechuga, repollo, brócoli, trigo, cebollas (algunas cultivadas para su semilla) prosperan bajo los manzanos. Cuando se cosecha un cultivo, otro ocupa su lugar, en complejas rotaciones sobre pequeños espacios. No aplican productos químicos, pero el grupo fabrica caldo mineral sulfocálcico y abonos orgánicos líquidos para mejorar el suelo, prevenir las enfermedades de los cultivos y mejorar la producción y calidad de los manzanos y de las hortalizas.

El grupo ha cosechado verduras cuatro veces y las ha vendido directamente a los consumidores en ferias organizadas por la AAF (en una canasta solidaria y saludable) por un total de 4.380 bolivianos (635 dólares).

Yo visitaba la finca agroforestal de Sipe Sipe con un pequeño grupo organizado por la AAF y algunos de sus aliados. Algunas de las lechugas, cebollas y tomates de la finca terminaron en una bañera durante nuestra visita, para hacer una ensalada para los visitantes, parte de un fabuloso almuerzo (con papas frescas y cordero cocido bajo tierra en un pampaku) ofrecido a un precio modesto. Los productos cocinados en el sitio y vendidos informalmente en la finca probablemente no se contabilizan. Después del recorrido por la finca y antes del almuerzo, Marcelina organizó una mesa para vender algunas verduras. Se mantuvo ocupada apuntando cada transacción mientras comprábamos pequeñas bolsas de tomates y otros productos por cantidades menos de un dólar cada una.

La venta de medio kilo de tomates es tanto trabajo como la venta de veinte toneladas de arroz. Una finca pequeña tiene muchas más ventas que una grande y se requiere mucho trabajo administrativo para hacer un seguimiento de los productos que no se venden porque van a parar como semilla, para alimentar a los animales o a la mesa de la familia.

El costo:beneficio de un campo convencional es más simple de tabular: tanta mano de obra, maquinaria, semillas y productos químicos, todos comprados, y el rendimiento de un solo cultivo medido con relativa facilidad. Sin embargo, esto no cuenta toda la historia. La pérdida de suelo debido a la erosión, o el carbono y nitrógeno a la atmósfera, o la contaminación por la escorrentía de los fertilizantes, todos ellos tienen un costo, aunque a menudo se desestimen como “externalidades”.

Un sistema agroforestal, como la hectárea de manzanas y hortalizas que visitamos comienza con una gran inversión en riego y terrazas. Muchos de los insumos son mano de obra, o abonos caseros, y su costo no siempre se cuenta. Los manzanos aún no han dado fruto, y algunas de las verduras pueden escaparse de la cuenta del contable. Sin embargo, aquí las “externalidades” tienen una contribución positiva y valiosa: se está creando el suelo, la contaminación química es nula y los medios de subsistencia se enriquecen a medida que los agricultores locales, en su mayoría mujeres, aprenden a trabajar juntas para producir alimentos saludables para vender. Las comparaciones económicas clásicas con las explotaciones convencionales no tienen en cuenta estos beneficios.

Incluso una pequeña granja puede tener mucho que considerar al estimar los rendimientos, con muchos cultivos y actividades y servicios ambientales. Hasta que no aprendamos a medir la eficiencia ambiental y la rentabilidad financiera de las granjas agroforestales o agroecológicas de manera adecuada, nunca se verán tan bien como realmente son.

Para leer más

Un informe reciente de la FAO (Organización de las Naciones Unidas para la Alimentación y la Agricultura) concluye que los datos sobre el rendimiento son muy pobres para poder comparar la agricultura convencional (sobre arado, con uso intensivo de químicos) con la agroecología, una agricultura que vas más allá de la orgánica, con conservación del suelo y respeto para las comunidades locales.

Resumen y recomendaciones del informe del GANESAN sobre Agroecología y otras innovaciones (19 de junio 2019). Roma: FAO. http://www.csm4cfs.org/es/summary-recommendations-hlpe-report-agroecology-innovations/

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