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A long walk home April 12th, 2020 by

In Bolivia, a draconian shutdown went into place almost as soon as the first coronavirus cases were reported in the country in March. When the universities were shut, one 20-year old student, José Andrés Romero, tried to stay on in the city of Sucre, where he had been studying building construction. He was working part-time as a welder’s assistant, but when his employer closed shop, José Andrés could no longer afford the rent on his room. Then he ran out of food.

The buses had been stopped, so José Andrés would have to walk home, to his grandfather’s house in the village of Motaya, 90 kilometers away.

Just leaving the city was a challenge. In Bolivia we are only allowed out of the house one morning a week; everyone is assigned a day from Monday to Friday, depending on the last number of one’s national ID. When it was José Andrés’s turn to leave his room, on a Wednesday, he left at 7:40, carrying water and cooked pasta, the last of his provisions.

He avoided the road most of the time, taking short cuts. He wasn’t very sure of the path, so he used the GPS on his phone to guide him. After running out of water, he drank from a stagnant pond, which made him vomit. Weakened, and with no houses in sight, José Andrés kept walking. The mountains and the canyons blocked his phone signal most of the way. Then he remembered what his grandmother had taught him, that the stars set in the west, and this helped guide his way.

At 11 at night, when José Andrés climbed to a ridge, he saw the lights of the town of Presto, near his village, and he also got a phone signal. He called his cousin, who came with a friend on motorcycles to pick José Andrés up from the road. It was one in the morning on Thursday when they got home.

The municipality put José Andrés in quarantine for two weeks, but his family will feed him, and then he will be able to help with the farm work and wait out the quarantine.

This story puts a face on what is blandly called rural-urban migration. One of the most viable strategies for rural migrants is to go to the city after graduating from high school, to attend university. Young people from the countryside work their way through school and after graduation build a career in the city. These hardworking, resourceful kids are the future of their country. Yet they are so under-appreciated that national leaders can close their universities and shut down the bus system, without even offering the students the dignity of a ride home.  



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 EcheverrĂ­a 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


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 tĂ©cnicas correctas pueden aumentar el carbono del suelo del 1% (tĂ­pico de los suelos degradados) al 4% (como en los bosques vĂ­rgenes) o incluso hasta el 6%. Existen muchas de esas tĂ©cnicas y tiene diversos nombres, como “agricultura de conservaciĂłn”, “agroecologĂ­a” 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 (cĂłmo 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 IntroducciĂłn (una introducciĂłn a una serie de 12 videos sobre la agricultura de conservaciĂłn)

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.


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

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