“Everything had been lost,” read the transcripts. “We just had fear, fear, fear.”
In Pichilín, a small town in Colombia’s Montes de María, decades of violence have left lasting scars—and an unpleasant threat to the population’s future.
Up until the early 2000s, the Montes, which lie on the Caribbean coast of Colombia, were an epicenter for guerrilla warfare—the result of the centuries of violence that have marked Colombia’s history since its bloody and turbulent birth. Colombia has been systematically ravaged by periods of civil warfare rooted in turmoil between its conservative and liberal parties. In the early 1970s, a broken treaty between the parties precipitated Colombia’s history with guerrilla warfare and drug trafficking, leading to the formation of left-wing extremist groups, including the Fuerzas Armadas Revolucionarias de Colombia, commonly known by their acronym FARC. By the late 1990s, drug production—the guerrilla’s primary means of financial support—and unemployment were running high, leading to the emergence of far-right paramilitary groups such as the Autodefensas Unidas de Colombia (AUC), whose mission was to combat the guerrilla warriors by any means possible, including by terrorizing citizens suspected to be allied with them.
The Montes have been marked by dozens of armed forces, from the FARC to the AUC. “It never occurred to us that they would come here,” an interviewee said of Pichilin, a town so small it doesn’t appear on Google Maps. Her story is one of many: a paramilitary group arrived one afternoon with no warning. Four weeks pregnant, she was easy prey for the guerrilleros, who took her to a house with a few other women and left her on the lower level. “I heard one of the gun shots [sic] . . . Men took them, they laid them face down, they used all their barbarity and of all the bad words that could pass through one’s mind, imagine.” She did not elaborate. “We thought it was the end of us.”
Even after the AUC was dissolved in 2006 and the FARC signed a ceasefire treaty in 2017, Pichilin continued to struggle with the legacy of the conflict. “[We] lived in a period of fear, of loneliness,” said the interviewee, “A car would come into the town and we would run.” But isolation and paranoia were not the only blights brought by the conflict.
A heavily agricultural area, the Montes struggled with famine throughout the conflict. “We are going to die of hunger here,” an interviewee remembers thinking. Indeed, due to the destabilizing nature of guerilla warfare, many families moved to urban areas to keep from starving, a problem Colombia continues to grapple with. But, during the early 2010s when residents in the Montes returned to their homes, they discovered a strange phenomenon—one that could overturn their return to stability.
On the slopes of El Carmen de Bolívar, a town across the valley from Pichilin, avocado farmers faced a novel problem. Below their feet, the roots of their trees grew black and brittle; by their heads, the avocados remained small, hard, and—most problematically for the farmers—impossible to sell. Their trees had been infected with ink rot, which afflicts the root tips first, but quickly spreads upward into the crown of the tree. As the rot takes hold, the roots exude a thick, black substance; the leaves wilt and discolor in a process called leaf necrosis: the death of leaf cells. When leaf fall finally comes, the avocados are both unripe and rotting.
The movement of people and their associated pets, livestock, and gear is correlated with a higher chance of pathogen spread. During the conflict, the Montes were alive with activity. It is possible that one of the many paramilitary groups passing through Montes spread the pathogen to the area; the chlamydospores could have been caught anywhere from the crevices in their boot soles to the dirt in their tires. Further aggravating the spread of the pathogen would have been the lack of agricultural management due to the widespread displacement, meaning that farmers couldn’t see the initial signs of the infection and were powerless to stop the spread.
The culprit is Phytophthora cinnamomi, “one of the most devastating plant pathogens known” according to a 2018 study. P. cinnamomi is an oomycete, a fungus-like organism that breaks down organic matter. Like many oomycetes, P. cinnamomi can lie dormant within an infected plant, and it is this, as well as its adaptability to different environments, that makes it so dangerous: P. cinnamomi’s chlamydospores—spores that it uses to spread, like seeds—can survive up to six years without nutrients, allowing the pathogen to spread throughout an extended period of time. When a chlamydospore is finally exposed to soil with a certain mix of amino acids and root-originated compounds, it germinates to produce sporangia. These structures can be thought of as spore factories; they make zoospores, spores that specialize in entering plants by breaking through non-woody tissue. Once the zoospores have entered a plant, they begin to rot the tissue—the root. And, if that wasn’t deadly enough, the pathogen then emits toxins that stop water flow, leading to leaf necrosis. P. cinnamomi’s devastating effects make it a well-known danger in the United States, Europe, and Australia, but in El Carmen de Bolívar, the largest town in the region known as Montes de María, it is an entirely new kind of killer.
“Us here in Montes de Maria,” said the interviewee, “we are fans of agricultural production. Ultimately, the production is for us to live.” The residents of Pichilín specialize in growing yuca, cassava, maize—in fact, they depend on it; in El Carmen de Bolívar, residents depend on avocados to live. With the arrival of P. cinnamomi, all their livelihoods are threatened. But the ramifications of P. cinnamomi’s new presence in rural Colombia go beyond the livelihoods of the small farming community of the Montes. P. cinnamomi is, after all, notorious for a reason; it has decimated the sweet chestnut forests of Europe, endangered dozens of endemic species in Australia, and put over four thousand more species at risk. If the pathogen were to extend its borders in the Montes for only a few more miles, it would spill into the Los Colorados sanctuary, one of three protected forest areas within the Montes. Besides being a IUCN protected area, Los Colorados is home to over 208 species of birds and forty-four species of mammals, among which is the endangered grey-belled monkey. All those species, however, depend on the flora of Los Colorados—105 species of trees alone in an area of 1000 hectares—to which the appearance of P. cinnamomi would be a death knell.
In previous cases, farmers have used integrated disease management methods to stave off P. cinnamomi: a combination of several common methods, such as pesticide or fertilizer use, which are calculated to give the most effective results while mitigating adverse environmental impact. However, these methods are designed for large-scale farming operations; they include strategies such as adding potassium silicate to soil and irrigating with the addition of pesticides. Not only are these methods potentially harmful to other ecosystems in the Montes area, they are impractical and expensive to implement on a small scale. A more holistic approach—one more appropriate for small farms—would be more effective for the farmers in the Montes. However, these kinds of approaches are not nearly as immediate or successful. And that’s a problem.
After decades of conflict, Colombia’s economy has been severely damaged. The recent influx of Venezuelan refugees—a mostly jobless and resource-depleted population—has only aggravated Colombia’s economic plight. And, when the pandemic hit, Colombia implemented strict lockdown procedures—but with a population that mostly deals in in-person employment and cash payments, thousands were put into severe financial straits. Conflict—this time spurred by civilians—is threatening to break out again. All of this means that the Colombian government is eager for an economic boost, one which could easily be provided by more large-scale farming operations, which usually grow sugar cane, coffee, or oil palm monocultures. The small-holder farmers of the Montes, a region famous for its fertility, are already under pressure to turn their land over to large-scale farming operations, but the Colombian government will sooner seize their land for companies that can afford integrated disease management methods than invest resources in solutions for small-scale farmers.
The consequences of losing Colombia’s subsistence agriculture communities could be severe, however. As large-scale farming operations push small farmers to urban areas, the economic recovery Colombia is undergoing could take a significant blow. In the countryside, farmers have the freedom to set their own rates, giving them a modicum of control over their income; when they move to cities, however, they are outpriced by urban sellers. This means that many displaced families end up unemployed or with irregular employment, exacerbating poverty, malnutrition, and housing issues already prevalent in Colombia’s low-income urban areas.
One method, however, could save the future of Colombia’s small farming communities. Biological control agents, or BCAs, are a developing frontier in agriculture, and are being used to mitigate pests, boost plant growth, and strengthen environmental tolerance. Traditionally, biological control methods have entailed pitting natural enemies against each other: if an area were to become infested by invasive mice, a biological control method would dictate sending in a natural enemy—like hawks or snakes—to cut back the invasive population. This kind of biological control has its critics; species released to mitigate invasive groups often become invasive themselves, precipitating a hellish cycle of initial control and subsequent loss of it. Recently, however, biocontrol has extended to strains of microorganisms and GMOs. It is this kind of BCA that could be the key to stopping P. cinnamomi.
In a 2020 study published in the Journal of Integrative Agriculture, a group of researchers led by David Granada found that a strain of Serratia bacteria could be used to combat P. cinnamomi root rot. The strain was selected from “indigenous antagonistic isolates”—antagonistic here meaning anti-oomycetic—found in avocado trees from the region of Antioquia. (It is worth noting that while some indigenous avocado varieties have shown resistance to P. cinnamomi, Colombia’s position as an international monolith of avocado production prevents it from straying too far from the known commercial varieties.) Granada and his team watered infected seedlings with a water/oil emulsion containing Serratia, distilled water, palm oil, and traces of other compounds. What they found could be groundbreaking: the Serratia strain was so effective in combating the infection that, when Granada and his team re-examined the seedlings only ten days later, there were no traces of P. cinnamomi left: not only had the strain halted the infection, it had completely eliminated it.
But, as the interviewee put it, “agriculture is not assured.” Granada’s BCA solution could be a lifesaver for the farmers of the Montes—and the surrounding forest—but there is still much to do. Part of the problem with BCA is that strains will react differently in certain climates or ecosystems; it may be that Serratia is not as effective in the Montes as it is in Antioquia. If the strain fails, if it is inaccessible, or if it is unaffordable, the Colombian government, desperate to regain economic footing after decades of internal conflict, will look away as their land is turned to cash-crop fields. “In this country, everything is corrupt,” the interviewee said. “Everything is contaminated.” With BCAs, that contamination could be mitigated, but the future is still uncertain.
“A New Threat in the Montes: The Legacy of Conflict in Colombia’s Agricultural Communities” is the fourth of six pieces in ROOTED, which won the Gold Medal Portfolio Award for writing sponsored by the New York Times in the 2023 Scholastic Arts & Writing Awards.