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Of chestnuts and cherries August 30th, 2015 by

Do you ever wonder why they stop you at the airport or the border crossing and ask if you have any plants?

The American chestnut was once the largest and most common tree in the eastern woodlands of the USA. Its loss led to a greater understanding of the importance of quarantine to protect agricultural and forest trees.

In the early twentieth century, the chestnut blight fungus arrived in North America from Asia. Chestnut blight was first spotted in 1904, in the Bronx Zoo. The chestnut trees started to die, much to the dread of the American people, who liked the tall, handsome tree, and valued its wood for furniture making. The disease was widespread by 1911 and the trees were basically gone by the 1950s.Here and there, a few ancient chestnut stumps still sprout branches. A sixty acre (24 hectare) stand planted by settler Martin Hicks, in West Salem, Wisconsin (outside of the tree’s natural range) is the largest remnant left.

Rescue efforts failed, but the US Department of Agriculture (and more recently the American Chestnut Foundation) never gave up, and have recently bred a resistant variety of chestnut, which they are planting on public forest lands, within the chestnut’s historical range. The new tree is 15/16’s American, but was crossed with Asian trees that are resistant to the blight. The new variety seems to be resistance to the blight.

At least the chestnut disaster was a learning experience. In 1910, the Japanese government gave the US a gift of 2000 ornamental cherry trees. American plant pathologists in Washington inspected the trees, observing that some of them had insect pests, fungi and nematodes. The Department of Agriculture burned the entire shipment from Japan, to protect American fruit trees from disease. It was an early experience with quarantine, isolating plant imports to protect the receiving country from disease.

Destroying the trees was the right thing to do from an agricultural point of view, but it was a diplomatic crisis. The State Department telegraphed a note of apology to the Japanese government. It was a model of frankness and tact, acknowledging that “It has been found necessary to destroy all of the cherry trees presented by the municipality of Tokyo for the use of this city. The reports of several experts of the Department of Agriculture show the trees to be badly infested with the root gall worm, certain fungus diseases and insect pests, some hitherto unknown in this country, whose introduction might result in future in enormous detriment to trees and agriculture generally.”

flowers and Washington monument

The Japanese graciously responded by sending 3,000 more cherry trees, healthy ones this time. They still bloom gloriously once a year around the Tidal Basin Pond, in a large, but neat circle between the Jefferson and Lincoln monuments, in Washington DC. Diplomatic and agricultural disasters were avoided.

The tragedy of the American chestnut taught plant pathologists the importance of inspection and quarantine, which they used in the case of the Japanese cherry trees, still blooming a century later. Now most countries have airport and border inspectors to screen plants coming into the country. It may seem like an inconvenience, but it is a small price to pay to keep the trees standing.

Further reading

Campbell, C. Lee, Paul D. Peterson & Clay S. Griffith 1999 The Formative Years of Plant Pathology in the United States. St. Paul, Minnesota: The American Phytopathological Society. 427 pp.



The best banana August 23rd, 2015 by

Two weeks ago we read about the banana growers of the Chapare, in Bolivia. One of their problems was black Sigatoka, an introduced fungal disease first documented in Fiji. Sigatoka attacks the banana leaves, killing them and sometimes the plant. Fruit losses can be devastating.

In 2003, a large, USAID-funded project was doing participatory research with farmers in the Chapare. Researchers and extensionists visited the fruit-growing associations and selected farmers willing to have an experimental trial on their land.

In the standard method, researchers establish a block on each farm, with several “replicates” of each treatment. But here they did it differently; each farm would be a replicate, with just one example of each of the treatments. This made the experiment easier for the farmers to manage, and easier for visitors to appreciate the difference between the four treatments and the control group.

25 deshojandoTwenty five farmers replicated different combinations of fungicides and pruning (cutting off the diseased parts of the leaves). The control group was left up to the farmers, who were supposed to conduct their normal activities. Implicitly, the researchers expected the farmers to handle the control group like any ordinary piece of commercial banana land. The whole experiment with its 25 replicates would be evaluated statistically.

I didn’t design the experiment, but I liked it, because it seemed to have the right balance of scientific rigor and real-life flexibility. But when the statistician ran the numbers, he was shocked. The treatment with the least disease and the most bananas turned out to be the farmer control group.

03 stacked bananasWhen the farmers had heard the researchers talking about a “farmer’s control,” the smallholder banana growers went out of their way to beat the scientists. Some farmers were able to site their control group on the land most recently cleared from the forest. All of the farmers were learning as they went along. Instead of lamely repeating their actions of the previous year, they adapted as they went along. They learned from the researchers’ treatments, and applied fungicides in the farmer control, and carefully removed the dead leaves from the plants.

The farmers had creatively incorporated new ideas immediately, in the first year of the experiment. As Paul Richards said years ago, agriculture is a performance. And a performance can be turned into a competition. In this case the researchers had some initial frustration when they saw the numbers going in unexpected directions, but in the end, everyone won, because they still grow bananas in the Chapare.

Further Reading

Bentley, Jeffery 2003 Desarrollo Participativo de TecnologĂ­a en el TrĂłpico de Cochabamba. Report for Development Alternatives.

Mushroom collecting: more than a hobby August 16th, 2015 by

When I buy a coffee or chocolate in London there’s a fair chance I’ll see a picture of a farmer or her family. I won’t see a photo of the person who collected the truffle or the chanterelles I buy.

Termite mushrooms BiasaMost food comes from cultivated or managed sources, but there are also substantial amounts hunted or gathered from the wild. The most valuable wild mushrooms include chanterelles, porcini (Boletus edulis), matsutake (Tricholoma spp.) and truffles. They and many other mushrooms need to grow on living, woody plants, where they form fungus-roots or mycorrhizae. It’s a mutually beneficial association that makes forests a fertile place for mushroom collecting.

The success of the wild mushroom trade depends entirely on collectors and traders. Yet these people are the least well-known aspect of an industry that provides a significant source of income for mostly poor people. One estimate put the in-season retail value of the most valuable wild mushrooms at more than $2 billion.

Selling termitomycesClearly there is more to rural livelihoods than agriculture, as this short account will explain. In Malawi women play an important role in picking wild mushrooms which they can sell and eat. They are surprisingly nutritious, with around 15-20% protein by dry weight. But for collectors it’s more important to sell than to eat, at least in in Malawi and neighbouring countries with miombo (dry) woodland.

Malawi benefits from an accident of nature: trees in the miombo woodland form mycorrhizae with edible species of mushroom. So too do the pine forests of the Pacific Northwest of North America, which extend from northern California to British Columbia. This became a new source of matsutake, a highly prized wild mushroom in Japan, filling a critical gap caused by Japan’s declining production of matsutake from shrinking native pine forests, caused by disease, pollution and felling.

The North American matsutake is not quite as tasty as the Asian species, yet such was the demand from Japan from the 1990s onwards that new job opportunities quickly increased. In Oregon the collectors include local people who once worked in forestry (a declining industry) and migrant labourers from Mexico, Cambodia and Laos. These groups had little or no family history of collecting wild mushrooms.

Stall 4 with berries behindA recent study by Mattia Cai and colleagues at the University of Padua in Italy provides a fresh account of wild mushroom collecting in Finland, where the government encouraged collection of wild mushrooms after the Second World War because of fears of food shortages and to generate rural jobs. In other countries collectors and traders operate in uncertain legal conditions and try to avoid officials. In Finland, wild mushroom collecting is exempt from taxes and anyone can do it.

The study divided collectors into professional, ordinary and recreational groups. The professionals were the smallest group selling to a local company, but provided over two thirds of the mushrooms (mainly porcini). The professionals collected for 45 days in the year of the study and earned €1200, around 5% of the average net annual household income for Finland.

In Spain, a separate study found that a family could earn over €200 in a day from collecting níscalos (Lactarius deliciosus), compared to the minimum monthly wage of just over €400. My colleague Miriam de Román’s family was from the village where traders bought the níscalos, so people were willing to share information. Miriam’s aunt told us: “If anyone says they’re doing it for a hobby, don’t believe them.”

There are concerns that commercial collection is unsustainable because of fears of over-picking. Scientific trials show this is highly unlikely, yet clear legal and regulatory frameworks are needed to ensure fair and legitimate use of natural resources. Authorities in Finland, the US and Canada issue licenses and set quotas, working closely with collectors and traders. In Italy, truffle collectors are tested on collection methods before they can let their dog loose to sniff for buried treasure.

In Africa and Asia, collection of wild mushrooms is, well, rather a wild affair. In miombo Woodland, pickers compete with charcoal makers and others for right of access. Authorities often fail to resolve disputes or to do so consistently. Fairer regulation would benefit everyone, but particularly the many people who depend on wild gathered foods as a valuable source of income and food.

Further reading

Boa, E. 2011. From Chipho to Msika: an introduction to mushrooms, trees and forests. In Mushrooms in Forests and Woodlands. Resource Management, Values and Local Livelihoods, edited by Cunningham AB, Yang X. London: Earthscan. Read more

Cai, M., Pettenella, D. and Vidale, E. 2011. Income generation from wild mushrooms in marginal rural area. Forest Policy and Economics: 13, 221-226

de Román M. and Boa E. 2006. The marketing of Lactarius deliciosus in Spain. Economic Botany 60: 284-290. Read more

Going bananas August 9th, 2015 by

It is one thing to organize smallholders, and quite another to tell them what to do, as we see in this story of how commercial banana growing in Bolivia succeeded and failed at the same time.

The rain forest of central Bolivia, in an area called the Chapare or “the Tropics of Cochabamba” was home to Amazonian peoples like the Yuqui and the Yuracaré until the 1960s, when Bolivia started an ambitious colonization program, supported by USAID, to send Andean peoples to clear the forest and grow crops. One of the most successful of these crops was coca, the raw material for cocaine. A few coca bushes had been grown in the Chapare since the 1700s, and possibly for a long time before that. But that coca was used to make a stimulating chew. By the 20th century coca was entering the global narcotics trade, as cocaine.

Pushed out by drought and closing tin mines, colonists flooded into the Chapare and the coca supply blossomed. This was too much for the US government which in 1983 started a new policy based on the big stick of police repression of coca, and the carrot of “Alternative Development” which meant growing other crops, like bananas and peach palm. USAID built all-weather, cobblestone roads, and organized some of the colonists in associations to grow bananas.

In her 2004 book on the School of the Americas (a US military training camp for Latin American soldiers), anthropologist Leslie Gill discusses Alternative Development. On page 194 she wrote:

“Replacing coca with bananas is in fact a peculiar proposition. In the Chapare there are no stable roads or packing facilities, and technological assistance through the alternative crop development program is rudimentary or non-existent. To believe that peasants of a remote inland region could become competitive exporters is therefore a difficult stretch of the imagination.”

Yet agriculture thrives on imagination, and even at the time Gill’s book was published, the packing sheds were up and running. Gill is an expert on soldiers, not farmers.

Going bananas 1Up to now, all of the association members have access to a packing shed. Little hand rails running from the groves to the sheds make it easier to carry the banana bunches to be packed. The members own their own individual patches of bananas, planted next to each other in large contiguous blocks, near the packing sheds.

If the bananas were real, so was the police repression of coca, and much more brutal. President Evo Morales tells that when he was a young, local leader and a coca grower, the narcotics police (UMOPAR, trained by the US DEA—Drug Enforcement Administration) took him to the woods and beat him senseless, and left him there. He would have died if his friends had not gone looking for him, he told historian Martín Sivak. Other settlers have told me similar stories, about being beaten and robbed by UMOPAR.

The coca growers responded to the repression by organizing roadblocks that shut down all traffic in and out of the region, blocking the main industrial city of Santa Cruz from the government in La Paz, but incidentally forcing the banana growers to watch their fruit rot on the plants.

aa Going bananas 2When Evo became president of Bolivia in 2006; he threw out the DEA, tamed UMOPAR, and in 2008 forced USAID to close its operations in the Chapare, but that was for political not agronomic reasons. The fruit growers’ associations continued, and the extension work to support them was taken over by the local municipal governments, which have always been allied with the coca growers and with Evo. The national government created a program to inspect the bananas, train growers, and certify that the bananas were disease and insect-free, which also eases exports.

The FAO estimates that Bolivia produced 210,000 tons of bananas in 2012. Exports in 2013 were worth $27 million (mostly by truck, to Argentina). Bananas are a success story, but they haven’t eliminated coca, as the US government hoped. Coca and bananas have now found a peaceful coexistence in the Chapare. The local municipalities are intimately tied to their peasant constituents; the mayors are farmers themselves. The local people easily saw that new crops created a diverse, healthier local economy. They opted for bananas and coca, not instead of.

Further reading

Blanes, José 1983 De los Valles al Chapare: Estrategias Familiares en un Contexto de Cambios. Cochabamba: CERES. 191 pp.

Gill, Lesley 2004 The School of the Americas: Military Training and Political Violence in the Americas. Durham: Duke University Press. 281 pp.

Jones, James C. 1990 “The Chapare: Farmer Perspectives on the Economics and Sociology of Coca Production.” Binghampton, New York: SARSA/IDA. 86 pp.

Sivak, MartĂ­n 2008 Jefazo: Retrato ĂŤntimo de Evo Morales. Santa Cruz, Bolivia: El PaĂ­s. 336 pp.

The sugar palms of Angkor Wat August 2nd, 2015 by

Archaeologists and zealous groundskeepers have cut many ancient sites down to the bare stones, but with the green grounds and palm trees in Angkor Wat one can almost imagine what the place must have looked like when people lived there.

Archaeologists extract information on plant use through various methods, such as analyzing bas-reliefs and wall paintings (see our earlier blog on Egyptian corn). They analyze pollen and identify plant remains found in soil, comparing what they find with information on useful plants from history books and ethnographic accounts of contemporary people.

Upon reading The Kingdom and People of Siam, written by Sir James Bowring in 1857, the French naturalist and explorer Henry Mouhot decided to undertake an expedition to Indochina and obtained financial support from the Royal Geographical Society and the Zoological Society of London. While the 31-year old professor made accurate drawings of the site, he wrongly assumed that the site was built by an earlier civilization than the Khmer, while in fact the very same civilization which built Angkor was still living there.

In the late 1850s, the majestic sugar palm (Borassus flabellifer) was thriving at Angkor Wat. This may be one reason why all of Mouhot’s line drawings, which depicted the temple from various angles, showed the sugar palm that can still be seen at the complex today.

The Khmer people have probably grown the sugar palm at the site around Angkor Wat since ancient times, in an unbroken tradition. Although many societies have lived without sugar, according to Sidney Mintz, the anthropologist of sugar, no people has ever willingly given up sugar after having tasted it.

While sugar cane and sugar beets dominate the lucrative sweetener market, many trees also have economic value as source of sugar. In many developing countries various palm trees are an important source of sugar for local people. Palm sugars are produced by either tapping the sap from the inflorescence of the tree or by tapping the tree trunk itself by making slits in the bark (the way rubber is tapped) and letting the sweet juice ooze into a pot. The juice is boiled down into a syrup, which is then sold as is, or allowed to crystallize into various shapes and sizes.

“We continuously look for creative ways to improve our sweeteners and starches, and biochemical processes occurring in nature are an important source of inspiration,” says Anthony DeLio, Chief Innovation Officer of Ingredion, which provides ingredients for the food, feed, beverage, brewing, and pharmaceutical industries.

Demand for palm sugars may be rising rapidly due to changes in global market economies and food habits. Sugars from palm trees are not refined and overly processed like white sugar. They are richer in nutrients. Sugars from trees are also more slowly absorbed by the blood so they don’t put stress on the pancreas to produce large amounts of insulin to keep blood sugars down.

When working and living in Bangladesh in the early 2000s, I saw people harvesting juice from the “khejur gach” or wild date palm (Phoenix sylvestris). Local vendors sell chunks of the crystallized blocks of the sugary “gur”, which comes in various yellowish- brown shades. People traditionally use un-refined sugars to make indigenous sweet dishes, such as paesh (rice boiled in milk with cardamom, nuts and raisins) and sandesh (a dessert made with paneer and condensed milk). Gur is also used in different types of cakes or pithas, and different types of snacks, such as tiler khaja (a treat made of sesame seeds and sugar), naru (balls made from coconut, milk and sugar). The desired unique flavor of each of these foods is part of the rich Bengali culture.

If demand for palm sugars rises, sustainably increasing the yields of these palm trees will require a better understanding of the best ways to manage them; and learning from smallholder farmers will be crucial.

White sugar, high fructose corn syrup and other addictive sweeteners have contributed to all sorts of problems like obesity, diabetes and cardiovascular disease. A shift towards healthier sugars is likely to continue, but it will be important for manufacturers not to overstate their benefits.

Some governments are starting to think of ways to curb sugar abuse. For example, last week the Belgian government agreed to introduce a sugar tax. Whether this will lead to more healthy food habits remains to be seen. Remembering successful campaigns in the past to curb tobacco use, communication and educating consumers will be as crucial as raising the price of sugar.

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