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Encouraging microorganisms that improve the soil February 16th, 2020 by

Vea la versión en español a continuación

We have written earlier in this blog about “Effective Microorganisms®” or EM, a branded, commercial preparation. In both of those previous stories, people were using EMs in pig pens, to reduce the odor and to quickly turn the manure to a rich, black compost. 

This week I learned how you can culture your own microorganisms, using some simple equipment and a few inexpensive ingredients. Ing. Abrahán Mujica showed me and a small group at his agroecology course that you can start by collecting some leaf litter. We gathered the leaves and top soil from the base of two or three molle trees in the city of Cochabamba.

We put some 5 kilos of leaf litter and black soil on a plastic table. We added a kilo of raw sugar and a kilo of bran (rich in proteins), to feed the microorganisms, and just enough water to turn the mix to a paste. It should be just moist enough that it will release a couple of drops when you press it in your hand

As we mixed up the ingredients, a smell like bread yeast soon filled the room.

“Smell the yeast!” Abrahán said. “The yeast are the first microorganisms to respond to the sugar.”

“Not just yeast,” I said. “There must be 10,000 species of microbes in there.” Abrahán happily agreed.

We filled a third of a 20-liter bucket with this paste, and covered it with plastic bags, tied on with a rubber tie, to keep out the air. The mix will rot if it is exposed to the air, Abrahán stressed. Fermentation is without oxygen.

After a month, Abrahán will mix the fermented paste with water in a 200-liter barrel, seal it again for another month, and then drain off the water, which by then will be full of microorganisms.

He filters this solution through an ordinary cloth and bottles the liquid for sale. The label reads “The Life of the Soil”. It can be sprayed on the soil to make it healthier, or added to compost to speed up decomposition, or used as fertilizer on plant leaves. He said it is intended mainly for soil that has been killed by pesticides, to bring the soil back to life.

Abrahán’s home also doubles as a small shop, where he sells ácido piroleñoso (liquid smoke distilled during charcoal making—which is mixed with water and sprayed onto crops as natural insect and fungus control). He also makes potassium soap (which he makes by mixing potassium sulfate with cooking oil), sulfur-lime blend, Bordeaux mix, and other products for protecting plants without toxic chemicals.

Although Abrahán makes the products he sells, he is happy to teach others. On his agroecology course, he teaches others his trade secrets about how to make each product. There will always be lots of people who don’t want to mix these brews. And those who do make their own will also help to make the world a better place, by reducing the use of toxic pesticides, which Abrahán explains are a danger to farmers and consumers.

Related blog stories

Farming with trees

Effective micro-organisms

Smelling is believing

Related videos

Good microbes for plants and soil

Better seed for green gram

FOMENTANDO MICROORGANISMOS QUE MEJORAN EL SUELO

Por Jeff Bentley

16 de febrero del 2020

Hemos escrito antes en este blog sobre “Microorganismos Efectivos®” o EM, una marca comercial. Los dos blogs anteriores explican el uso de EMs en camas de cerdos para reducir el olor y ayudar a la descomposición del estiércol. 

Esta semana aprendí cómo uno puede multiplicar sus propios microorganismos, usando un equipo simple y unos pocos ingredientes baratos. El Ing. Abrahán Mujica me mostró a mí y a un pequeño grupo en su curso de agroecología. Recogimos tierra vegetal o sach’a wanu, como decimos en Bolivia, del pie de un molle, en plena ciudad.

En una mesa de plástico, pusimos como 5 kilos de sach’a wanu. Añadimos un kilo de chancaca (azúcar moreno) y un kilo de salvado (cascarilla de cereal rica en proteínas), para alimentar a los microorganismos, y sólo el agua suficiente para convertir la mezcla en una pasta, que al apretarla, debe soltar un par de gotas.

Mientras mezclábamos los ingredientes, un olor a levadura de pan llenó el ambiente.

“¡Sientan la levadura!” Abrahán dijo. “La levadura es el primer microorganismo que responde al azúcar y nutrientes”.

“No sólo la levadura”, dije. “Debe haber 10.000 especies de microbios ahí”. Abrahán estuvo plenamente de acuerdo.

Llenamos un tercio de un tacho de plástico de 20 litros con esta pasta y lo tapamos con hojas de plástico, atadas con una liga de goma, para evitar que entre el aire. La mezcla se pudrirá si se expone al aire. Abrahán recalcó que la fermentación es sin oxígeno.

Después de un mes, Abrahán la mezclará con agua en un turril de 200 litros; lo sellará de nuevo por otro mes, y luego drenará el agua, que para entonces estará llena de microorganismos.

Él filtra esta solución a través de un paño ordinario y embotella el líquido para su venta. La etiqueta dice “La vida del suelo”. Puede ser fumigado en el suelo para devolverle vitalidad, o puesto en la abonera para acelerar la descomposición, o aplicado a las plantas como abono filiar. Dijo que está destinado principalmente a los suelos que se han muerto por los plaguicidas, para devolverles la vida.

La casa de Abrahán también funciona como una pequeña tienda, donde vende ácido piroleñoso (humo líquido destilado durante la fabricación de carbón vegetal, que se mezcla con agua y se fumiga sobre los cultivos para controlar los insectos y los hongos de forma natural). También hace jabón potásico (que elabora mezclando sulfato de potasio con aceite de cocina), caldo sulfocálcico, caldo bordelés y otros productos para proteger las plantas sin productos químicos tóxicos.

Aunque Abrahán fabrica los productos que vende, le gusta enseñar a los demás. En su curso de agroecología, enseña a otros sus secretos sobre cómo hacer cada producto. Siempre tendrá mercado, porque habrá mucha gente que no quiere hacer estas mezclas. Y aquellos que hacen la suya también ayudarán a hacer del mundo un lugar mejor, reduciendo el uso de agroquímicos mucho más tóxicos, que Abrahán está convencido son un peligro para los agricultores y consumidores.  

Previamente en nuestro blog

La agricultura con árboles

Effective micro-organisms

Smelling is believing

Videos relacionados

Buenos microbios para plantas y suelo

Better seed for green gram

Farming with trees January 19th, 2020 by

Vea la versión en español a continuación.

On a rocky hillside an hour from the city of Cochabamba, agronomist Germán Vargas points out a molle tree. It’s growing from a crack in a sandstone boulder with little or no soil. Native trees are well adapted to such conditions and don’t need much to survive, Germán observes.

Molle can be cut for good firewood, but it also casts an inviting shade, with a thick carpet of fallen leaves. Trees grown on farms also have multiple uses. Some have deep roots that bring up nutrients from beneath the top soil. Even in places like Cochabamba, with a long dry season, many trees stay green all year round. The trees have found water to keep their leaves moist, despite the bone-dry subsoil. Germán explains that farming with trees, or agroforestry, mimics natural forests, where rich soils are created without irrigation or fertilizer.

Four years ago, Germán and two colleagues bought some land to put their ideas on agroforestry into practice. They now have 1500 apple trees in a 4-hectare orchard, on a former onion farm, where the intensive use of chemical fertilizers and pesticides had depleted the soil of nutrients.

Germán and his friends bought some apple seedlings from a local nursery. They chose improved Brazilian apple varieties, such as Eva and Princesa, which do well in the highland tropics of South America, where it can get cool, but does not freeze.

Germán and his colleagues plant a few more trees every year. They start each new planting by digging a trench every two to three meters (depending on the slope), to let water infiltrate the soil. They throw the soil just uphill of the trench to create a barrier, slowing down the runoff of water and trapping sediment.

Germán is careful not to scrape the soil surface with hand tools; the top soil is so thin that rough handling could remove it all. They add a little compost to the soil, mimicking a natural forest, where fallen leaves and trees rot and release nutrients back into the soil. However, forests also have an understory, so potatoes, maize, lettuce, amaranth, rye and other plants are sown between the trees. After planting the vegetables, a straw mulch keeps down the weeds.

Other trees are planted among the apples, including natives like molle and exotic species, which are monitored to see if they can make a positive contribution. Germán brought seed of the chachafruto tree from Colombia, for example. The plant is adapting well. When the only date palm in Cochabamba, another non-native species, dropped a cluster of dates in a city park, Germán salvaged the seed and planted some on the farm. The non-fruit trees make useful leaf litter, adding nutrients and helping to keep the soil moist.

The apples were remarkably free of mildew, mites, fruit flies and other common pests, but even if they were to appear, Germán avoids using pesticides. The team managing the orchard makes a spray with cow manure, raw sugar, bone meal, sulfur, ash and lime. Reasoning that all stone has mineral nutrients, they add a little “rock flour,” made by grinding a soft, local, sedimentary stone (shale). A culture of beneficial microorganisms is added to ferment the mix in sealed drums. The agroforesters culture the microorganisms themselves, but they get the starting culture in the local forest, bringing in a few handfuls of fallen leaves that have started to decompose. The sulfur and the lime come from the farm supply store. This sulfur blend is sprayed about 5 times a year on the trees, and it seems to be working, since the apples have almost no pests, except for birds, and the annual plants are thriving.

This innovative agroforestry system needs regular attention and it is obviously a lot of work, especially at first, because it is established by hand, without machinery. Some of the radishes have gone to seed, and in a few beds the weeds are lush and healthy, waiting to be cut down for the next vegetable crop.

Farmers can learn from forests to make better use of water, conserve the soil and manage pest and disease naturally, thanks to the diversity of plants. Farming with trees can yield a good harvest of fruits and vegetables, while building and sustaining soils.

Related blog stories

Apple futures

What counts in agroecology

Gardening against all odds

Enlightened agroecology

Watch some related videos

SLM02 Fanya juu terraces shows how to make infiltration trenches, that form terraces.

SLM03 Grevillea agroforestry

SLM08 Parkland agroforestry

Scientific names

The molle tree is Schinus molle

The chachafruto tree (widespread in South America) is Erythrina edulis

Note

Sulfur deficiency is a problem in apples. The symptoms are similar to nitrogen deficiency, including pale leaves. Sulfur deficiency can be corrected by sprays (Westwood 1993: 200-201).

Westwood, Melvin Neil 1993 Temperate-Zone Pomology: Physiology and Culture. Third edition. Portland, Oregon: Timber Press.

Acknowledgements

Thanks to Germán Vargas, Marcelina Alarcón and Freddy Vargas, the agroforesters. Germán is the executive administrator of the NGO Agroecología y Fe.

LA AGRICULTURA CON ÁRBOLES

En una ladera rocosa a una hora de la ciudad de Cochabamba, el ingeniero agrónomo Germán Vargas señala un molle. Crece en una grieta de una roca arenisca, con poca o ninguna tierra. Los árboles nativos están bien adaptados a estas condiciones y no necesitan mucho para sobrevivir, observa Germán.

El molle hace buena leña, pero también da una rica sombra, con una gruesa alfombra de hojas caídas. Los árboles en el agro también tienen múltiples usos. Algunos tienen raíces profundas que traen los nutrientes de debajo del suelo. Incluso en lugares como Cochabamba, con una larga época seca, muchos árboles se mantienen verdes durante todo el año. Los árboles han encontrado agua para mantener sus hojas húmedas, a pesar del subsuelo seco. Germán explica que la agricultura con árboles, o la agroforestería, imita a los bosques naturales, donde se crean suelos ricos sin irrigación ni fertilizantes.

Hace cuatro años, Germán y dos colegas compraron un terreno para poner en práctica sus ideas sobre agroforestería. Ahora tienen 1500 manzanos en un huerto de 4 hectáreas, en una antigua granja de cebollas, donde el uso intensivo de fertilizantes químicos y pesticidas había agotado los nutrientes del suelo.

Germán y sus compañeros compraron algunos plantines de manzana en un vivero local. Escogieron variedades mejoradas de manzanos brasileños, como Eva y Princesa, que se desarrollan bien en los trópicos de las alturas de América del Sur, donde puede hacer frío, pero no se congela.

Germán y sus colegas plantan unos pocos árboles más cada año. Comienzan cada nueva plantación cavando una zanja cada dos o tres metros (dependiendo de la pendiente), para dejar que el agua se infiltre en el suelo. Lanzan la tierra justo cuesta arriba de la zanja para crear una barrera, frenando el escurrimiento de agua y atrapando el sedimento.

Germán tiene cuidado de no raspar la superficie del suelo con herramientas; el suelo negro de la superficie es tan delgado que sin tener cuidado sería posible quitarlo todo. Añaden un poco de abono al suelo, imitando un bosque natural, donde las hojas y los árboles caídos se pudren y liberan nutrientes de nuevo al suelo. Sin embargo, los bosques también tienen un sotobosque, por lo que las papas, el maíz, la lechuga, el amaranto, el centeno y otras plantas se siembran entre los árboles. Después de plantar las verduras, un mantillo de paja mantiene las malas hierbas.

Entre las manzanas se plantan otros árboles, incluyendo especies nativas como el molle y especies exóticas, que son monitoreadas para ver si pueden hacer una contribución positiva. Germán trajo semillas del árbol de chachafruto de Colombia, por ejemplo. La planta se está adaptando bien. Cuando la única palmera datilera de Cochabamba, otra especie no nativa, dejó caer un racimo de dátiles en un parque de la ciudad, Germán recuperó algunas semillas y las plantó en la finca. Los árboles no frutales botan hojas, añadiendo nutrientes y ayudando a mantener el suelo húmedo.

Las manzanas estaban notablemente libres de mildiu, ácaros, moscas de la fruta y otras plagas comunes, pero incluso si aparecieran, Germán evita el uso de pesticidas. El equipo que maneja el huerto fumiga con un biol hecho de estiércol de vaca, chancaca, huesos molidos, azufre, cenizas y cal. Razonando que toda piedra tiene nutrientes minerales, le agregan un poco de “harina de roca”, hecha al moler una piedra sedimentaria suave, local (lutita). Para fermentar la mezcla, agregan un cultivo de microorganismos buenos a los tambores sellados. Los agroforestales cultivan sus propios microorganismos, pero obtienen la cultura inicial en el bosque local, trayendo unos pocos puñados de hojas caídas que han comenzado a descomponerse. Compran el azufre y la cal en la tienda agropecuaria. Fumigan el biol con azufre unas 5 veces al año en los árboles, y parece que funciona, ya que las manzanas casi no tienen plagas, excepto los pájaros, y las plantas anuales están prosperando.

Este innovador sistema agroforestal necesita atención regular y obviamente es mucho trabajo, especialmente al principio, porque se establece a mano, sin maquinaria. Algunos de los rábanos han empezado a echar semilla, y en algunas camas las hierbas silvestres son exuberantes y saludables, esperando ser cortadas para el siguiente cultivo de hortalizas.

Los agricultores pueden aprender de los bosques a hacer un mejor uso del agua, conservar el suelo y manejar las plagas y enfermedades de forma natural, gracias a la diversidad de plantas. La agricultura con árboles puede producir una buena cosecha de frutas y verduras, a la vez que construye y mantiene los suelos.

Otros blogs sobre el tema

Manzanos del futuro

Lo que cuenta en la agroecología

Un mejor futuro con jardines

La luz de la agroecología

Videos relacionados

SLM02 Terrazas fanya juu muestra cómo hacer zanjas de infiltración, que forman terrazas.

SLM03 Agroforestería con grevillea

SLM08 Agroforestería del bosque ralo

Nombres científicos

El molle es Schinus molle

El chachafruto (árbol bien distribuido en Sudamérica) es Erythrina edulis

Nota

La deficiencia de azufre es un problema común en los manzanos. Los síntomas son parecidos a los de la deficiencia de nitrógeno, incluso las hojas pálidas. La deficiencia de azufre puede ser corregida con fumigaciones (Westwood 1993: 200-201).

Westwood, Melvin Neil 1993 Temperate-Zone Pomology: Physiology and Culture. Third edition. Portland, Oregon: Timber Press.

Agradecimientos

Gracias a Germán Vargas, Marcelina Alarcón y Freddy Vargas, por su ejemplo con la agroforestería. Germán es el administrador ejecutivo de la ONG Agroecología y Fe.

Poisoning our friends October 20th, 2019 by

Except for entomologists, no one knows more about insects than farmers. Wherever researchers have bothered to talk to smallholders about insects, whether in Honduras, Nepal, or among the Dogon of Mali, or the Kayapó of the Brazilian rainforest, we see that rural people know the names of hundreds of insects and spiders. This is especially true of critters that are conspicuous (such as the big ones that are active during the day) or those that make themselves important, e.g. by eating crops.  

However, a recent, quantitative global literature review by Kris Wyckhuys and colleagues confirms that farmers know little about beneficial insects, especially in industrialized countries. As we saw in this blog last week, it is fairly easy to notice toads and other relatively large animals eating insect pests. Many farmers know that birds, frogs and cats are natural enemies of pests. Yet Wyckhuys found that worldwide, farmers mention on average only 0.9 insects or spiders that help to control insect pests.

Farmers can have sophisticated knowledge of certain, individual insect species. For example, Paul Van Mele and colleagues have described Vietnamese farmers who used weaver ants to control pests in fruit orchards. Such cases are, however, disappointingly rare. Weaver ants are big, diurnal, and easy to spot in their treehouse nests sewn together from leaves. Farmers were also motivated to watch weaver ants because they prey on insects like fruit flies in high-value orchards.  Most other natural enemies of insect pests, “farmers’ friends” go unnoticed. Hardly any rural people know about other common natural enemies of pests, such as parasitic wasps, insect-eating fungi and nematodes.

Farmers tend to use more pesticides in cash crops, and know fewer natural enemies for these crops, than in food staples. The use of pesticides is growing worldwide, while the pest problems are as bad as ever. Farmers are born experimenters, but to find alternative to pesticides, they need to know more about the natural enemies of insect pests.

Wyckhuys suggests that some of the world’s half trillion-dollar subsidies for agriculture could be devoted to agro-ecological education. Farmers will never find alternatives to pesticides unless they understand that most insects are beneficial. As farmers use insecticides to kill pests, they unwittingly poison their friends, the insects that eat and kill those pests.

Further reading

Van Mele, P 2008 “The importance of ecological and socio-technological literacy in R&D priority setting: the case of a fruit innovation system in Guinea, West Africa.” International Journal of Agricultural Sustainability 6: 183–94.

Wyckhuys, K.A.G., K.L. Heong, F. Sanchez-Bayo, F.J.J.A. Bianchi, J.G. Lundgren and J.W. Bentley 2019 “Ecological Illiteracy Can Deepen Farmers’ Pesticide Dependency.” Environmental Research Letters 14: 093004

Related videos

Promoting weaver ants in your orchard

Weaver ants against fruit flies

The wasp that protects our crops

Killing fall armyworms naturally

See also the many other farmer learning videos about Integrated Pest Management on www.accessagriculture.org.

Related blog stories

Toads for watermelon

Battling the armyworm

Biological pest control in the Galapagos forest

No word for legume September 1st, 2019 by

Vea la versión en español a continuación

I remember a story from grad school about a people in the Amazon Basin who had no word for “parrot”, because they knew the names of all the individual species of parrots.

I was reminded of that this week in Peru, where I was teaching a course on how to write fact sheets and video scripts for a popular audience.

My students are seasoned professionals, and one group was writing a fact sheet about planting legumes to fix nitrogen from the air, as a non-chemical way to improve the soil, a crucial concept for ecological agriculture. Along with the students, I struggled to say “nitrogen-fixing legumes” in words that everyone knows. “Nitrogen” was the easy part, it’s like urea fertilizer, which most smallholders know about.

But “legume” was trickier. It’s a botanical term. Like the parrot-watchers in the Amazon, smallholders in many parts of the world have a word for each species of legume, but no one word for all legumes.

“We could say ‘plants that produce pods.’” I suggested helpfully.

“No,” one of my students said, rejecting my idea out of hand.

That’s one of the advantages of teaching adults, the students know more than the teacher about a lot of topics. In this case, the student is an agronomist who has worked with farmers and legumes in northern Peru for a full career. He explained that some of the best legumes for fixing nitrogen, like alfalfa or the wild garrotilla, have pods so small that people fail to see them.

In the end, we wrote “legume” and then followed it with examples like beans and peas.

Then we drove out to the prosperous village of Piuray, about an hour from Cusco on the road to the Sacred Valley. The smallholders of Piuray value formal education. They are proud of their large, two-story school. Some of the local people work in the city as lawyers and engineers.

But after asking several local people to read our fact sheet, they often looked up and said “What’s a legume?”

Our examples had not been good enough to explain the concept. And there is no simpler word for legume. The simplest word for legume is “legume.”

This matters when writing for a global audience, because people all over the world, from Peru to Pakistan grow legumes, but different species.

In the end, the authors of this fact sheet realized that there was no short and simple way to say “nitrogen fixing legumes.” So they said “Legumes are plants like clover, lupin, vetch and alfalfa that capture nitrogen from the air in little nodules, which are pink or white balls or in the roots. The nitrogen is then used by the rest of the plant.”

Some terms have no simpler synonym, but they can be defined and explained, in words that everyone knows.  

Scientific names

Garrotilla is Medicago hispida

Acknowledgements

Thanks to Edgar Olivera and Ing. Alfredo Tito, both of the Grupo Yanapai, and to Dr. Ana Dorrego of the Centro de Investigación de Zonas Áridas (CiZA) of the Universidad Nacional Agraria La Molina and of LEISA, la Revista de Agroecología. They are writing a script for a video on pasture management. I have learned a lot from them in a week of working and writing together.  Our script writing course was generously supported by The McKnight Foundation’s Collaborative Crop Research Program (CCRP).

HACE FALTA UNA PALABRA PARA LEGUMINOSAS

por Jeff Bentley, 1 de septiembre del 2019

Recuerdo una historia de la universidad de posgrado sobre un pueblo en la Amazonía que no tenía una palabra para “loro”, porque conocían los nombres de cada especie de loro.

Me acordé de eso esta semana en el Perú, donde enseñaba un curso sobre cómo escribir hojas volantes y guiones de video para una audiencia popular.

Mis estudiantes son profesionales experimentados, y un grupo estaba escribiendo una hoja volante sobre el sembrar leguminosas para fijar el nitrógeno del aire, como una forma no química de mejorar el suelo, un concepto crucial para la agricultura ecológica. Junto con los estudiantes, luché para decir “leguminosas que finan nitrógeno” en palabras que todo el mundo conoce. El “nitrógeno” fue la parte fácil; es como la urea, que la mayoría de los campesinos conocen.

Pero “leguminosa” era más difícil. Es un término botánico. Al igual que los observadores de loros en la Amazonía, los pequeños agricultores en muchas partes del mundo tienen una palabra para cada especie de leguminosa, pero ninguna para todas ellas.

Sugerí “Podríamos decir ‘plantas que producen vainas'”.

“No”, dijo uno de mis estudiantes, rechazando de frente mi idea.

Esa es una de las ventajas de enseñar a los adultos; frecuentemente los estudiantes saben más que el profesor. En este caso, el estudiante es un ingeniero agrónomo que ha trabajado con agricultores y leguminosas en el norte del Perú durante toda su carrera. Explicó que algunas de las mejores legumbres para fijar el nitrógeno, como la alfalfa o la garrotilla silvestre, tienen vainas tan pequeñas que la gente no las ve.

Al final, escribimos “leguminosa” y luego la seguimos con ejemplos como frijoles y arvejas.

Luego nos dirigimos a la próspera comunidad rural de Piuray, a una hora de Cusco en el camino hacia el Valle Sagrado. Los pequeños agricultores de Piuray valoran la educación formal. Están orgullosos de su gran escuela de dos pisos. Algunos de los habitantes locales trabajan en la ciudad como abogados e ingenieros.

Pero después de pedirle a varias personas locales que leyeran nuestra hoja volante, a menudo levantaban la vista y decían “¿Qué es una leguminosa?”

Nuestros ejemplos no habían sido suficientes para explicar el concepto. Y no hay una palabra más sencilla para leguminosas. La palabra más simple para leguminosas es ” leguminosas”.

Esto es importante cuando se escribe para una audiencia global, porque gente de todo el mundo, desde Perú hasta Pakistán, cultiva leguminosas, pero especies diferentes.

Al final, los autores de esta hoja volante se dieron cuenta de que no había una forma corta y sencilla de decir “leguminosas que fijan nitrógeno”. Así que dijeron: “Las leguminosas son plantas como el trébol, el tarwi, la vicia, y la alfalfa que capturan el nitrógeno del aire a través de nódulos, que son bolitas rosadas o blancas en las raíces. Luego el nitrógeno es aprovechado por el resto de la planta.”

Algunos términos no tienen sinónimos más sencillos, pero pueden ser definidos y explicados, en palabras que todo el mundo conoce. 

Nombre científico

Garrotilla es Medicago hispida

Agradecimientos

Agradezco al Ing. Edgar Olivera y al Ing. Alfredo Tito, ambos, del Grupo Yanapai, y a la Dra. Ana Dorrego del Centro de Investigación de Zonas Áridas (CiZA) de la Universidad Nacional Agraria La Molina y de LEISA, la Revista de Agroecología. Ellos están escribiendo un guion para un video sobre el manejo de los pastos. En una semana de convivencia y redacción he aprendido bastante de ellos.  Nuestro curso de redacción de guiones recibió el apoyo generoso del Programa Colaborativo de Investigación sobre Cultivos (CCRP) de la Fundación McKnight.

Roundup: ready to move on? August 25th, 2019 by

At our local garden shop, in northeast Belgium, I recently overheard a conversation between the shopkeeper and a young customer, who asked about Roundup®. Since glyphosate, the active ingredient in the herbicide, was banned in Belgium for home use (see note below), a new glyphosate-free Roundup is now aggressively promoted in garden centres. The original Roundup can only be used for professional farming, so the shopkeeper told the customer that her husband is continuously asked to go and spray people’s ornamental home gardens. Even chemical habits can be hard to kick.

When it is my turn at the counter (I am looking for organic chicken feed), I tell the shopkeeper that I just returned from an international conference where American professors revealed how various ingredients of Roundup can be related to male infertility, cancer, Alzheimer and at least 40 other human diseases. She took in the information without being shocked and countered that many people have since resorted to home-made remedies like vinegar to kill weeds, which she preposterously claimed did much more harm to the soil than commercial products. Apparently, the people who sell chemicals, even at the retail level, can become jaded about their dangers.

Both in developed and developing countries, very few people think it necessary to protect themselves when spraying pesticides. People either cannot read, fail to make the effort to read the label or ignore the risks.

While debates on cause-effect relationship can last for decades (the tobacco lobby successfully denied the carcinogenic effects of tobacco for decades, knowing all the while that smoking was a killer), the scientific presentations at the international conference I attended also revealed the shortcomings of official systems that have been put in place to protect our public health. For one, toxicity trials before new products are released only look at short-time effects, whereas diseases of mice (and humans) often show symptoms after years of chronic exposure, as the toxins build up in the body. Equally important, official tests are only done on the active ingredient, not on the full product as it is sold and used.

Protected by intellectual property rights, companies are not obliged to reveal and list the ingredients of the inert material that makes up the bulk of herbicides and pesticides. Laboratory tests showed that one of the ingredients in Roundup is arsenic, which is at least 1000 times more toxic than glyphosate in itself. In short, the glyphosate-free Roundup is still as toxic as before, only it does not show in official tests.

The sad irony is that while the owner of the garden shop is busy spraying people’s gardens with Roundup, the government of Belgium spent millions of Euros to protect those same people, by cleaning the soil from the arsenic factory in Reppel, which was closed in 1971. Although scientific evidence was available that the soil and groundwater were heavily polluted with arsenic, zinc and other heavy metals, it took more than 30 years before the site was cleaned up, and apparently more work is still required.

Environmental damage, including pollution, soil erosion and biodiversity loss are hard to measure in simple economic terms. As Jeff mentioned in last week’s blog, environmental costs are often seen as “externalities” and not considered when calculating the cost:benefit of farms. This has given conventional farming an unfair advantage over organic or agroecological farming.

Although the narrow focus on a single active ingredient, such as glyphosate, may have been good to trigger a public debate around food safety and the danger of corporate interests in our food system, a more holistic approach to crop protection and food production is required that takes into account these externalities.

Managing weeds is a key challenge for farmers across the globe. While mulching, crop rotation, intercropping and green manures are all options, additional weeding may be required—often by appropriate, small machines. Alternatives to herbicides do exist. For commercial (conventional and organic) farmers affordable mechanical weeding technologies, based on precision technology, would make a huge difference.

For instance, the food processing industry has benefitted a lot from optic food sorting machines. In a fraction of a second, a stone the size of a pea can be removed from millions of peas. With a simple mobile app called PlantNet I can take a photo of any plant which immediately tells me what plant it is, even if I only have the leaves at hand and the plant is not yet flowering.

Despite what the industry wants to make us believe, farmers do not need herbicides. If countries are serious about public health, more research is needed to support non-chemical food production. Agricultural robots are getting better. In the near future it would be possible to engineer a wheeled robot that could systematically drive over a field, scanning for weeds, and eliminating them mechanically, even within crop rows.

If governments would invest more in alternatives to chemical agriculture and organise nation-wide campaigns (as they have done for decades to inform people of other health risks, such as smoking, and drinking and driving), farmers, gardeners and shopkeepers (like the lady near my village) would become more aware of the dangers of herbicides and more open to promoting and using alternatives.

As I walked out of the village garden shop without my organic chicken feed (she did not have it in stock for lack of demand), I realized that shopkeepers are happy to sell what people ask for, if enough people ask for it. I hope one day to go back and find them selling better tools for controlling weeds.

Further reading

Defarge, N., Spiroux de Vendômois, J. and Séralini, G.E. 2018. Toxicity of formulants and heavy metals in glyphosate-based herbicides and other pesticides. Toxicology Reports 5, 156-163.

First International Conference on Agroecology Transforming Agriculture & Food Systems in Africa: Reducing Synthetic Pesticides and Fertilizers by Scaling up Agroecology and Promoting Ecological Organic Trade. 2019, Nairobi, Kenya. https://www.worldfoodpreservationcenterpesticidecongress.com/

HLPE. 2019. Agroecological and other innovative approaches for sustainable agriculture and food systems that enhance food security and nutrition. A report by The High Level Panel of Experts on Food Security and Nutrition. www.fao.org/fileadmin/user_upload/hlpe/hlpe_documents/HLPE_Reports/HLPE-Report-14_EN.pdf

IPES-Food. 2016. From uniformity to diversity: a paradigm shift from industrial agriculture to diversified agroecological systems. International Panel of Experts on Sustainable Food systems. www.ipes-food.org

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