A railroad trestle runs over the Ventura River estuary, with stands of Arundo along the banks. <\/span>Kitra Cahana\/Undark<\/span><\/p>\n<\/div>\n This story was originally published by <\/em>Undark<\/a> and\u00a0is reproduced here as part of the\u00a0<\/em>Climate Desk<\/a>\u00a0collaboration.<\/em><\/p>\n In the spring<\/span>\u00a0<\/strong>of 2024, when Cy Tongate visited Shelby Park on the eastern bank of the Rio Grande in Eagle Pass, Texas, the area looked more like a warzone than a riverside park in need of weed control. Humvees and pickup trucks crowded the newly cut access roads; patrol boats planed across the river; large beige tents rose from the soccer fields, shielding National Guard troops from the searing Texas sun. Checkpoints blocked the park\u2019s entrances, and along the riverbank an ad hoc wall of shipping containers and razor wire marked the boundary of the United States. Standing on top of the fortification, lookouts peered into Mexico over tufts of Tongate\u2019s ultimate target:\u00a0Arundo donax<\/em>, a tall, bamboo-like invasive plant that sprouted at the water\u2019s edge.<\/p>\n The military buildup was part of Texas Gov. Greg Abbott\u2019s \u201cOperation Lone Star,\u201d a multi-pronged deployment of the state\u2019s National Guard and Department of Public Safety personnel that had begun in 2021 and ramped up in subsequent years, eventually overtaking Shelby Park in January of 2024. Abbott, displeased with then-president Joe Biden\u2019s border policies and determined to stem what, in his telling, had become an \u201cinvasion\u201d of migrants, banned federal Border Patrol officers from entering the park, considering them too lenient. The move sparked tensions between state and federal authorities, and Shelby Park\u2014named for a pro-slavery activist and Confederate general\u2014became a flashpoint in the national immigration debate.<\/p>\n Into this tangle slipped Tongate, a young, mid-level bureaucrat with the Rio Grande Vegetative Management Program, a project run by an obscure state agency called the Texas State Soil and Water Conservation Board. He had visited the park sporadically since 2022, pursuing his own inconspicuous piece of the governor\u2019s wider border vision: the reduction of\u00a0Arundo donax<\/em>, known locally as giant reed or carrizo cane, which had aggressively colonized not only Shelby Park but nearly everywhere else in the Rio Grande Basin as well. The plant grew so expansively that it was impeding border operations\u2014migrants could hide in the dense thickets\u2014and authorities wanted it gone.<\/p>\n Working in the park, however, proved challenging. Tongate was frequently ensnared in the bureaucracy of the military command structure, with flummoxed National Guard troops calling up and down the chain of command to verify his clearance. The confusion, he said, sometimes led to troops mistaking his team\u2019s herbicide-spraying drones for drug-smuggling tools. Once, he recalled, a particularly paranoid National Guardsman accused him of spraying Agent Orange. Most consequentially, however, the jurisdictional turf war produced such a flurry of activity, with new roads and fences going up everywhere, that it activated the underground network of Arundo stems, causing the plant to grow more vigorously. It took Tongate five re-treatments to beat back the plant, and though most of it is gone now, upriver Arundo stands threaten to re-infest the area. \u201cThat\u2019s any government work,\u201d said Tongate. \u201cThere\u2019s a lot of futility.\u201d<\/p>\n The futility Tongate sometimes feels is perhaps commensurate with the enormity of the task before him. For thousands of years,\u00a0Arundo donax<\/em>\u00a0has spread across the globe, wreaking havoc on the riparian ecosystems it invades. The plant\u2019s kaleidoscopic utility\u2014it has been used by humans for everything from construction materials to musical instruments\u2014ensured its rapid territorial expansion as it followed human migrations, and infestations can now be found on every continent in the world except Antarctica. <\/p>\n Likely arriving in North America alongside Spanish colonizers in the 17th and 18th centuries, Arundo now bedevils waterways in at least 25 states, vigorously spreading through a form of asexual reproduction that results in vast thickets of genetic clones. In the areas it overtakes, Arundo often outcompetes nearly every native species, forming robust monocultures that destroy habitat, consume huge amounts of water, and pose increased risk of fires and floods. In California, where the plant was first rigorously studied in the 1990s, one scientist labeled it the \u201cgreatest threat\u201d to that state\u2019s riverside ecosystems. And in Texas, along the Rio Grande, the plant now covers tens of thousands of acres.<\/p>\n In embarking on his multi-year battle with Arundo, Tongate joined a long line of scientists, land managers, environmentalists, government officials, nonprofit workers, and others who have gone up against Arundo\u2014and mostly lost. At first, the failures had to do with the plant\u2019s remarkable tenacity and a poor understanding of how to kill it; efforts to mow, uproot, or burn it, for example, rarely worked. After scientists eventually developed an effective technique for eliminating Arundo in the early 1990s, however, attempts to control it continued to fail, not because of the plant\u2019s vigor or biological cunning, but rather because of humankind\u2019s myriad foibles.<\/p>\n Tangles of bureaucracy, ineffective coordination, underfunding, divisive science, two separate corruption scandals, and at least one ambush by semi-automatic gunfire have stymied attempts to address North America\u2019s Arundo infestations, leading to a sort of forever war. Borders\u2014between landholdings, counties, states, and nations\u2014often prove catastrophic for Arundo removal efforts, as jurisdictional squabbling, territorialism, and bureaucratic inertia foreclose on the possibility of keeping apace with a plant that pays no mind to lines on a map. A large-scale biological control program in Texas, which released similarly heedless predatory insects to attack the plant, may have surmounted some of those issues, but it has generated its own problems, as doubts have emerged over its efficacy and the quality of its science.<\/p>\n Despite the difficulties, Tongate maintains faith that those fighting against Arundo\u2019s spread will emerge victorious\u2014someday. \u201cI might be dead,\u201d he said, adding: \u201cOn a long enough timeline, what is it? Give me a long enough lever and I can move the world.\u201d<\/p>\n In the here and now, however, Tongate is humbled by the forces arrayed against him: \u201cFederal agencies. State agencies. Multiple different federal and state agencies, all fighting with each other. And our own internal corruption issue,\u201d he said. \u201cThe crooked timber of humanity.\u201d<\/p>\n For a long\u00a0<\/span>time, Arundo\u2019s obdurate spread was thought to have begun in the Mediterranean Basin. Carl Linnaeus, known as the father of modern taxonomy, first described the plant from samples collected in Spain and France, naming it in his landmark \u201cSpecies Plantarum<\/a>\u201d in 1753. Modern genetics, however, has traced Arundo\u2019s provenance to the Indus Valley, which stretches across modern-day Afghanistan, Pakistan, and India, and to the southern edge of the Caspian Sea, in Iran. One group of scientists wrote that the species \u201cmay represent one of the oldest and most persistent biological invasions.\u201d Sometime in antiquity, then, Arundo invaded the Mediterranean region, just as it later would the Americas.<\/p>\n The plant\u2019s success can partially be explained by its biology. A remarkably high capacity for photosynthesis allows Arundo to grow up to four inches a day and reach heights of more than 25 feet in a single year. Its height blocks sunlight from reaching other plants, and it reproduces through thick mats of underground stems, called rhizomes, that crowd out other species in the soil. The rhizomes, which look like webs of interconnected ginger, can sprout new shoots at each junction in the web, or node, leading to stands of Arundo so dense that visibility within them is reduced to mere feet. Moreover, if the rhizomes break apart, many of the separate pieces have the ability to form a new colony.<\/p>\n Arundo withstands droughts, relishes floods, and flourishes without regard to soil type or groundwater salinity. Its underground rhizomic labyrinth easily survives both frost and fire, and it is often the first plant to resprout following a blaze. Since its aboveground biomass fuels \u201cfirestorms,\u201d according to one scientist, this creates a feedback loop, further entrenching the plant\u2019s dominance. \u201cWe\u2019ve done a bunch of competition studies, where we manipulate light, water, nutrients, and it\u2019s always the winner,\u201d said Tom Dudley, a University of California, Santa Barbara ecologist who has studied Arundo for more than 30 years. \u201cNo matter what the mechanism of competition is, Arundo, it just outcompetes basically anything else.\u201d<\/p>\n Beyond its own impressive suite of abilities, however, Arundo long ago found an accomplice in its global spread\u2014human beings. Throughout history, people have used the reed to make weapons and fishing poles, furniture and toys, primitive pipe organs and flutes, baskets and mats. It has been employed as material for roofing, fencing, insulation, and adobe construction. Various medicinal traditions have claimed its efficacy as an anti-inflammatory, a diuretic, a blood-clotting agent, and a treatment for herpes. As far back as 5,000 years, the Marsh Arabs of ancient Mesopotamia built elaborate ceremonial buildings, called mudhif, from Arundo. Egyptian mummies have been found wrapped in Arundo leaves, while more recently, psychonauts have investigated Arundo as a source of the powerful psychoactive molecule\u00a0dimethyltryptamine<\/em>, or DMT. (The plant contains a small amount, but not at concentrations high enough to make it a worthwhile source.) And the natural reeds in instruments like saxophones and bassoons, as well as in clarinets like the one Dudley has played since childhood, are made exclusively from Arundo. Where humans have gone, so too has Arundo, ingratiating itself with its protean utility.<\/p>\n The plant likely arrived in the Americas alongside Spanish colonizers, and by the early 1800s it was being cultivated intentionally around Los Angeles for use as a building material and to stabilize ditches. From there, it quickly spread. By 1852, it had been observed in Texas watersheds, and by 1890, according to the US Geological Survey, it had reached as far east as New Jersey. The US Department of Agriculture\u2019s (USDA) Soil Conservation Service, a precursor to the modern-day Natural Resources Conservation Service, likely planted Arundo as an erosion control measure, oblivious to the damage it would cause. Valerie Vartanian, a former project manager with The Nature Conservancy in California who managed efforts to eradicate Arundo in the 1990s, said that their blunder allowed the plant to spread rapidly. \u201cIt had the opportunity then to really just take over,\u201d said Vartanian. \u201cAnd that\u2019s what it seemed to do.\u201d<\/p>\n By the late 20th century, it had proliferated dramatically, choking waterways from the East Coast to the West Coast. Rivers in Southern California like the Santa Clara, the Santa Ana, the Santa Margarita, the Salinas, and many others fell victim to particularly egregious infestations. Scientists in that state began to take notice, observing the plant\u2019s excessive water use, the increased fire risk it posed, and the havoc it wreaked on habitat used by endangered species like the least Bell\u2019s vireo and the Arroyo Toad. \u201cThere\u2019s something for everyone to hate about\u00a0Arundo donax<\/em>,\u201d wrote one ecologist.<\/p>\n In an effort to unite the burgeoning research, a scientist with The Nature Conservancy named Gary Bell co-founded an initiative dubbed \u201cTeam Arundo\u201d in the early 1990s. Team Arundo began connecting scientists and stakeholders, and organizing conferences to discuss the threat of Arundo invasion. With increased scrutiny, the severity of the problem began to crystallize. \u201cBy far the greatest threat to the dwindling riparian resources of coastal Southern California,\u201d Bell wrote in a 1997 paper, \u201cis the alien grass species known as\u00a0Arundo donax<\/em>.\u201d<\/p>\n But a problem soon emerged: Nobody knew how to kill it.<\/p>\n In California<\/span>\u00a0<\/strong>in January of 1993, following days of intense rainfall, an engorged Santa Margarita River breached a levee on the sprawling Camp Pendleton Marine base, sending a wall of water crashing through the airfield. The flood nearly killed a marine, who had to be rescued, unconscious, by his comrades, and damaged some 70 aircraft and other pieces of equipment. General Walter E. Boomer, touring the base in the wake of the deluge, told a reporter that \u201cwe probably have more damage here as a result of the flood than we did during Desert Storm.\u201d Bridges, roads, and a historic chapel were wiped out by the torrent, and damages were estimated to top $100 million. <\/p>\n According to Jason Giessow, an environmental consultant who worked extensively on the base in the aftermath of the flood, the models used to design the levee contained a crucial omission: They did not account for the presence of\u00a0Arundo donax<\/em>. \u201cIt\u2019s not acting like vegetation, where water\u2019s passing through it,\u201d said Giessow. \u201cIt\u2019s acting like it\u2019s poured concrete, so you have to raise the bed form like 6 feet, 9 feet.\u201d<\/p>\n The devastation was not contained to the military base. Bridges and roads in other watersheds were damaged too, often by massive clumps of Arundo becoming ensnared in bridge piers, causing water to back up and eventually overcome the structures. For those who had been paying attention to Arundo\u2014and to many who hadn\u2019t\u2014the 1993 flooding was a wake-up call. The Department of Defense, which was responsible for Camp Pendleton, committed significant resources to Arundo removal on the Santa Margarita, as did other agencies and organizations.<\/p>\n By the time Valerie Vartanian inherited the reins of Team Arundo, just before the flood, a sort of panicked mythology had taken hold around the plant. It couldn\u2019t be mowed; it couldn\u2019t be pulled up; areas cleared of Arundo were immediately re-infested. It was even rumored that the plant could be run through a chipper and each chip could resprout. Collaborating with other scientists, including Tom Dudley, who had co-founded a northern chapter of the initiative called Team Arundo del Norte, Vartanian set about investigating these rumors. Soon, a more evidence-based understanding of the plant emerged.<\/p>\n Each chip could not sprout, the scientists found. Only the underground rhizome junctions, or nodes, could sprout year round, while aboveground leaf nodes could also sprout, but only in the springtime when they often develop a rooting hormone. The plant could be treated with herbicides like glyphosate, especially during the fall when it would enter a period of dormancy. Although mowing didn\u2019t work on its own, the researchers found that the chemical could greatly facilitate access to the innermost portions of dense stands, and freshly cut Arundo was especially vulnerable to herbicide if applied within a two-minute window. What emerged from these experiments was a different picture of the plant\u2014one that showed that, at least with strict protocol, Arundo was not invincible. \u201cWe dispelled a lot of myths,\u201d said Vartanian.<\/p>\n Biologically speaking, in fact, the problem wasn\u2019t particularly complicated. To eradicate Arundo, teams simply had to start at the very top of the watershed and work their way down systematically. By doing this, they removed the possibility of re-infestation by vegetative fragments floating down from upriver. The Arundo had to be cut back enough to allow adequate coverage with the herbicide, and it usually required several treatments. Treatments worked better in the fall, and treating after flood and fire events greatly improved efficiency and reduced cost. Using this method, in the late 1990s and early 2000s, Arundo was mostly cleared in the Santa Margarita watershed, which includes Camp Pendleton, and in several other small to medium-sized watersheds in southern California.<\/p>\n In other watersheds, however, a troubling reality emerged. While Arundo treatment was simple enough in theory, in practice it proved dizzyingly complex. A thicket of bureaucratic and legal hurdles, often as dense and impenetrable as the plant itself, confounded Vartanian\u2019s efforts. In the Santa Ana watershed, for example, there were dozens of legal entities that had to unite behind the effort: landowners, regulatory agencies, water districts, land managers, businesses, non-governmental organizations, resource conservation districts, public works agencies. There were federal, state, county, municipal, and individual interests, each with their own mission and funding picture. A successful eradication program would need near-universal buy-in\u2014any holdouts would threaten the success of everything downstream. \u201cIt was so complicated,\u201d Vartanian said. \u201cThere were so many entities.\u201d<\/p>\n At first, regulatory agencies like the US Fish and Wildlife Service and the Army Corps of Engineers felt that removal of Arundo would trigger costly mitigation requirements such as habitat restoration, a perspective Vartanian fought hard to shift, arguing that Arundo removal was, in fact, itself a form of habitat restoration. She succeeded in bringing those agencies around to her viewpoint, but the permitting process for individual landowners remained daunting. Some landowners even felt they were being asked to act against their own interests. In removing Arundo, for example, they could be inviting the return of endangered species, which in turn would impose stricter regulations on their land use through the Endangered Species Act.<\/p>\n Other hurdles involved siloed interests: the mosquito control district that liked Arundo because it used up so much water it kept the mosquito population in check; the musical instrument reed industry that wanted to cultivate the plant; the Fish and Wildlife Service concerns over treating Arundo in the fall because the work might interfere with the breeding habits of the spadefoot toad. Alone, each of these hurdles could be overcome, but together they amounted to a herculean feat of bureaucratic juggling. The work had to be carefully coordinated and executed\u2014mapping the infestations, securing funds, obtaining landowner permission, advancing through the permitting process, conducting the work\u2014and if any element faltered it would threaten the entire endeavor.<\/p>\n Vartanian and her partners responded to these challenges by developing creative solutions. Beyond the regulatory agencies coming to accept Arundo removal as a form of environmental mitigation, programs were also established to incentivize landowners: an Arundo exchange initiative, where landowners could swap their Arundo for free willows; or a mitigation bank, where development projects could simply pay for mitigation work that had taken place elsewhere in lieu of having to do it themselves. Still, poor watershed-wide coordination and incessant funding woes stymied the work.<\/p>\n To help overcome this, Vartanian considered the possibility of establishing a watershed-wide endowment that Arundo removal projects could draw upon to sustain their work. This too, however, proved complicated. Such an endowment would require donors, a board, a financial adviser, and an administrative body\u2014it too would require money and coordination. The idea never moved forward.<\/p>\n Vartanian left her position at The Nature Conservancy in 1998, moving out of California for 11 years. When she returned to the state in 2009, she was dismayed by the lack of progress. In 2011, Giessow co-authored a report that surveyed 23 watersheds with Arundo infestations. Of those 23, only two had achieved an initial reduction of 90 percent or above. Six watersheds had achieved initial reductions of between 30 and 70 percent. The rest had not managed to reduce their infestations more than 30 percent, and several, including the Santa Clara River, had not been able to reduce Arundo at all. \u201cWe just don\u2019t learn,\u201d said Vartanian, adding: \u201cIt\u2019s just hard for us to work together these days. And it\u2019s getting harder.\u201d<\/p>\n Ensconced in a protective legal and bureaucratic web,\u00a0Arundo donax<\/em>\u00a0proved a far more formidable foe than its biology would have suggested. Discouragingly, too, the infestations that led to such consternation and disillusionment in California were, relatively speaking, quite small\u2014most contained fewer than 1,000 acres of infestation.\u00a0Arundo donax<\/em>\u00a0in the Rio Grande Basin, by comparison, covered tens of thousands of acres. And there, the watershed flowed through not just counties but entire states, and formed an international border with Mexico. The scale of the problem was staggering.<\/p>\n For some scientists, biological control\u2014the use of natural enemies such as predators, parasites, and pathogens to reduce the population of an unwanted species\u2014seemed to offer a solution. These agents paid no mind to borders, jurisdictions, or land ownership. Perhaps, some thought, they could simply fly above the crooked timber of humanity.<\/p>\n The history of<\/span>\u00a0using one species to control another dates back at least 4,000 years, with some major success stories as well as some catastrophic failures. (The cane toad, released in Australia to control a beetle pest, continues to wreak havoc on that country\u2019s ecosystem.) Today, though, most countries, including the US, require\u00a0rigorous processes<\/a>\u00a0to ensure the mistakes of the past aren\u2019t repeated. For a control agent to be deemed suitable, it must be shown to be host-specific\u2014capable of surviving on only the target species. <\/p>\n \u201cHost specificity testing has become really, really important,\u201d said Mark Hoddle, a biological control specialist who directs University of California, Riverside\u2019s Center for Invasive Species Research. \u201cYou want a natural enemy that\u2019s going to be really focused on the target.\u201d So when USDA scientists moved forward with a biological control program for\u00a0Arundo donax<\/em>\u00a0in the early 2000s, the first step was to try to identify such a host-specific natural enemy.<\/p>\n The search was far ranging, taking teams of scientists to Spain, Cyprus, Greece, India, and Nepal in search of suitable insects or pathogens. Eventually, consensus began to build around two species in particular:\u00a0Tetramesa romana<\/em>, a type of non-stinging wasp native to the Mediterranean region, and\u00a0Rhizaspidiotus donacis<\/em>, a scale insect. The wasp damages Arundo by laying eggs inside its stems, which causes the plant to develop abnormal growths, or galls, that can stunt and perhaps kill the shoots; the scale, meanwhile, feeds on the vascular tissue at the base of the shoots and the underground rhizomes, causing damage and weakening the plant over time. <\/p>\n In evaluating these organisms, the USDA team was concerned with two central questions. First, were they host specific (meaning, they would not affect other plants)? In both cases, it was clear that they were. Second, would they do enough damage to Arundo to be effective biological control agents? Here, the answers were less clear. \u201cWhat is that impact going to be under, you know, released conditions?\u201d said Tim Widmer, a scientist with the USDA\u2019s Agricultural Research Service who was involved in the early biological control effort. \u201cSometimes it\u2019s hard to judge, but we were pretty confident.\u201d<\/p>\n Around that time, in 2005, a USDA-ARS entomologist and biological control researcher named John Goolsby returned to his native Texas after a six-year overseas assignment in Australia. He had heard about the Arundo program through colleagues, and felt that the Rio Grande Valley would be an ideal location to implement the research. His superiors agreed, and Goolsby began to lead the Texas initiative.<\/p>\n The program that Goolsby inherited, however, was still small, hobbled by inadequate funding and insufficient personnel. The researchers before him had made headway in identifying suitable agents, but deploying those agents over such a large area would be a technically challenging and costly endeavor. Local stakeholders\u2014mostly agricultural interests concerned about Arundo\u2019s water usage\u2014supported the program but could contribute little to it. Fortunately for Goolsby, however, another interested party, one with deep pockets, had also taken an interest in the work. \u201cAs I started to work on this project,\u201d said Goolsby, \u201cabout a year later, you know, the national security angle popped up.\u201d<\/p>\n By the mid-2000s, increasing border militarization policies and the strategy of \u201cprevention through deterrence,\u201d which sought to funnel migrants away from urban crossing points and into more remote and dangerous areas, using the desert\u2019s lethality as a deterrent, had largely succeeded in their aims. Border Patrol personnel now pursued migrants along vast lengths of the Rio Grande, where the agents were frequently hampered by impervious tangles of Arundo. In a 2007 statement, the Department of Homeland Security, of which Border Patrol is a component, said that Arundo was \u201coverrunning border access roads, reducing visibility, and hiding illegal activities.\u201d Eager for a solution, DHS decided to pour roughly a million dollars a year, according to Goolsby, into the biological control program. That was, he said, \u201cthe tipping point.\u201d<\/p>\n Within the biological control community, the ethics of such a funding source remains a point of debate. Goolsby, for his part, was proud of the collaboration with DHS, and said that \u201cany kind of initial controversy just sort of melted away.\u201d Others like Hoddle, the UC Riverside biological control expert, viewed the funding as a shrewd way to accomplish noble goals, a sort of trojan horse for the benefit of the ecosystem. Scientists like Dudley, however, were critical of DHS\u2019s motives. \u201cI honestly do think it\u2019s patently racist,\u201d he said, adding: \u201cDHS doesn\u2019t like brown people. Sorry to put it that bluntly.\u201d Despite the differing viewpoints on DHS\u2019s intentions, however, the agency\u2019s involvement was seen by some in the field as perhaps a case where the interests of Border Patrol and those of ecologists happened to overlap.<\/p>\n The program accelerated rapidly. A\u00a02009 analysis<\/a>\u00a0by Goolsby and other researchers predicted that biological control would produce a 67 percent reduction in Arundo within two years, which, because of the plant\u2019s excessive water consumption, would lead to a return of $4.4 in savings for crop irrigation water for every $1 of public investment. In Washington, DC, the effort found a champion in Congressman Henry Cuellar from Texas\u2019s 28th district, who raised awareness of the issue and spearheaded fundraising. Goolsby, for his part, began taking measurements of Arundo biomass every 50 miles or so along 558 miles of the Rio Grande, from Del Rio to Brownsville, to establish a baseline. In a lab at the Moore Air Base, a deactivated Air Force facility in Edinburg, Texas, the scientists began mass rearing the wasps and scale insects, which had been imported from Europe.<\/p>\n Despite the forward momentum, however, an unexpected discovery occurred in 2008. Before they had a chance to release the insects, while surveying Arundo near Laredo and Eagle Pass, Goolsby found that a population of the wasp,\u00a0Tetramesa romana<\/em>, was already present. Other surveys revealed populations in multiple locations around Texas, from Austin to San Antonio, to several points along the Rio Grande. A few years earlier, Adam Lambert, then a postdoc in Tom Dudley\u2019s lab in California, had made a similar discovery in Arundo stands there. It was unknown where the wasps came from or how long they had been in North America. It was also poorly understood why they didn\u2019t seem to be damaging the plant\u2014perhaps they were a different genetic strain, or had not achieved sufficient numbers. But in neither California nor Texas did the insects seem to be having an impact on the plant\u2019s abundance.<\/p>\n Nevertheless, the biological control program forged ahead. Between 2009 and 2012, some 1.2 million wasps and 600,000 scale insects were unleashed upon the Rio Grande\u2019s Arundo infestation. To achieve sufficient dispersal, the wasps were placed under cold storage, put by the dozens into hundreds of paper boxes, and dropped from the hatch of a low-flying Cessna 206. As they fell, the wasps would thaw, exit the boxes, and enter the Arundo thickets. The planes flew three days a week, year round, for nearly four years. The scale insects, which could not be dropped from planes, were released at various points by ground teams. \u201cIt really welled up inside of you to realize you were having an impact,\u201d said Goolsby.<\/p>\n That impact seemed to be noteworthy, at least according to Goolsby\u2019s team.<\/p>\n In November of 2014, evaluating the same sites that had been measured for a baseline, the team found an average of 22 percent reduction of above ground Arundo biomass. The results were\u00a0published<\/a>\u00a0in a 2015 paper that concluded that \u201cthe Arundo wasp is having a significant impact as a biological control agent.\u201d A\u00a0subsequent paper<\/a>, co-authored by Goolsby and others, including another USDA-ARS scientist named Patrick Moran, looked at five of the original 10 sample areas and found an additional 32 percent reduction, for a total of 54 percent at those sites. When other locations were taken into account, the team arrived at a slightly different number, an estimated 45 percent reduction of overall biomass by the spring of 2016. A third paper found an additional 55 percent reduction in areas where the scale insect had been established versus sites where only the wasp had been released.<\/p>\n Based on those results, Goolsby deemed the program a success. In a\u00a02022 publication<\/a>, he and Moran, once again asserting a 54 percent reduction, estimated that the biological control program was saving up to $10.8 million per year in conserved water. Furthermore, the scientists noted, the program had increased visibility and improved access for law enforcement. In an interview last year, Goolsby said that the effort had also broken new ground scientifically. \u201cA lot of people were skeptical that a plant this aggressive and fast growing, and also a grass, you know, could be a suitable target for bio-control,\u201d he said. \u201cBut I think we proved that it could be.\u201d<\/p>\n But not everyone was convinced. In 2018, another scientist with the USDA named Allan Showler co-published a\u00a0paper<\/a>\u00a0that disputed the biological control program. Bluntly titled \u201cThe arundo wasp,\u00a0Tetramesa romana<\/em>, does not control giant river reed,\u00a0Arundo donax<\/em>, in Texas, USA,\u201d the paper showed that after five years of study, Arundo stands in Kerr County, Texas, did not seem to be impacted significantly by infestation with the wasp. The plant was still able to propagate, even from offshoots that had been damaged by the wasp, and the established shoots of Arundo were not killed by the wasp. \u201cT. romana\u00a0<\/em>is a parasite that is well-adapted to\u00a0A. donax<\/em>\u00a0by not killing stalks, reducing stand density, and hindering propagation,\u201d wrote Showler\u2019s team. \u201cHence, the exotic wasp is ineffective as a biological control agent against\u00a0A. donax<\/em>.\u201d<\/p>\n The paper went on to directly address what it viewed as flaws in Goolsby\u2019s methodology. First, changing hydrological conditions in the region could produce fluctuations in biomass, Showler noted, and hydrological data was not provided in the published results. Goolsby had briefly preempted this concern in the 2015 paper, stating that \u201chydrological conditions on the Rio Grande are fairly stable for giant reed,\u201d but he did not provide evidence for this claim. In a recent email, Showler, who retired from USDA-ARS in November of last year, wrote that the Arundo biomass reductions Goolsby\u2019s team observed \u201cmay have been more due to water availability than to the wasp.\u201d Additionally, Showler questioned Goolsby\u2019s method of evaluating biomass, and noted that the high variation in Goolsby\u2019s results from site to site meant that the purported decline was \u201cnot substantiated statistically.\u201d<\/p>\n Despite repeated requests, Goolsby declined to respond to these or any other criticisms of the biological control program.<\/p>\n Skepticism of the program, however, is not limited to Showler. Bernd Blossey, a widely cited biological control expert at Cornell University, said in an interview in September that it was impossible to determine whether the wasp caused a decline in Arundo biomass. \u201cWe have no idea whether that was a result of\u00a0Tetramesa<\/em>\u00a0or some other associated factor,\u201d he said, later adding: \u201cThere\u2019s no evidence that suggests that this is a giant success.\u201d Adam Lambert, Dudley\u2019s former postdoc who had discovered and studied populations of the wasp in California, said he also had doubts: \u201cI think a lot of us sort of found it a little bit questionable having such huge reductions when we\u2019re not seeing that in California.\u201d Lambert pointed to the lack of ongoing monitoring \u2014 essential to evaluate the long-term success of biological control \u2014 as a major flaw in the program. Dudley, for his part, was even harsher in his criticism. \u201cIn my mind,\u201d he said, \u201cit was a total waste of money.\u201d<\/p>\n Today along the Rio Grande, although there is no ongoing monitoring of the impact of the insects, USDA and Border Patrol are still committed to the biological control program. In Fiscal Year 2025, the federal government spent at least $4 million to treat Arundo, including funding work to \u201ctop\u201d the cane\u2014mow it at about one meter of height using enormous sawblades mounted on tractors. In addition to providing greater visibility for Border Patrol, the topping is intended to cause the Arundo to produce more sideshoots, which the wasps prefer. But according to Cy Tongate, the project coordinator with the Rio Grande Vegetative Management Program, even the Border Patrol agents ostensibly working to support the biological control program have lost faith in its efficacy. \u201cOur human eyes can\u2019t tell the difference,\u201d he said.<\/p>\n \u201cThe insects, I think, had a lot of cooperation from Border Patrol, a lot of support from Border Patrol and DPS at first,\u201d Tongate said. \u201cAnd just the lack of immediate results that could, you know, were obviously different to the human eye, kind of led to them losing some of that support.\u201d<\/p>\n The loss of faith, however, has not been accompanied by a shift in approach. \u201cMy guess would be it\u2019s a typical, classic bureaucratic case where something gets started and it\u2019s very hard to stop it, right?\u201d said Tongate. \u201cYou know, it becomes something that is somebody\u2019s job.\u201d<\/p>\n He put it another way: \u201cNothing\u2019s so permanent as a temporary government program.\u201d<\/p>\n Over the course<\/span>\u00a0of the 2010s, despite the differing viewpoints on the Texas program, Patrick Moran, Goolsby\u2019s main collaborator, attempted to initiate a similar program in California. He transferred to a unit specializing in biological control at a USDA facility in Albany, in the Bay Area, and began collecting and shipping thousands of wasps from established sites in Texas to his new lab. In early 2017, he hired a postdoc named Ellyn Bitume to collaborate on the project, and they began searching for locations to release the wasps.<\/p>\n The effort in California proceeded on a much smaller scale than the Texas program. DHS, whose funding had allowed the Texas scientists to scale up their operation rapidly, had no involvement in California\u2014Arundo didn\u2019t pose problems for Border Patrol in that state\u2014leaving Moran\u2019s team reliant on a much smaller allocation from USDA. Bitume, who was tasked with finding suitable release sites, encountered many of the same problems that had bedeviled Arundo control teams for decades\u2014the labyrinthine patchwork of landownership, for example, and the sundry attitudes of the landowners. As she put it: \u201cYou can imagine a female alone, showing up to an almond farm in Fresno in a government truck, asking this old guy if I can release wasps next to his almond farm. Wasn\u2019t always a very pleasant conversation, but I did eventually succeed.\u201d<\/p>\n The team secured nine sites across central and Northern California. Establishing the wasps, however, proved difficult. Northern California\u2019s climate was much dryer than Texas, and even that of Southern California where the wasps were also established, and Bitume suspected that the new climate caused the insects to struggle. At one point, she resorted to misting the stands of Arundo with a spray bottle in an attempt to replicate the more humid conditions of Texas. The team did eventually manage to establish populations at the majority of the sites, but the insects never thrived as they had in Texas, and their population density remained disappointingly low. Nevertheless, the scientists were keen to evaluate the effects of the wasps on the Arundo. \u201cWe were at the threshold to look at impact,\u201d Moran said.<\/p>\n But it was never meant to be. In January of 2025, the Trump administration took power, and Elon Musk\u2019s Department of Government Efficiency initiative started a cascade of funding cuts, layoffs, and agency restructuring. \u201cWe, as federal scientists, were under attack,\u201d said Bitume in an interview last August. \u201cThat\u2019s really what it felt like, every day. It was psychological warfare.\u201d <\/p>\n In the name of downsizing for the sake of efficiency, federal scientists were offered early resignation programs, and many, including Bitume and Moran, took them. \u201cAll of our long-term entomologists who have all the expertise and wisdom, and all of our younger scientists who had motivation and ambition, they\u2019re all gone,\u201d Bitume said, adding: \u201cIt\u2019s been devastating.\u201d Moran, who believes the jury is still out on whether biological control on its own can be effective in California, said that the research, at least for now, appears to have shifted to the academic realm.<\/p>\n Within academia, however, support for biological control of Arundo\u2014at least with the wasp and scale insect\u2014has waned. Dudley, initially an enthusiastic supporter of the approach, has changed his stance. \u201cI kind of evolved quite a while ago to thinking that insects weren\u2019t going to do it,\u201d he said. Similarly, his former postdoc, Adam Lambert, has also become skeptical, at least of the insects tried thus far. They both, along with other scientists, have expressed interest in exploring other biological control agents\u2014not only other insects, but perhaps even fungal or bacterial pathogens\u2014but that research has not progressed meaningfully. \u201cWe\u2019re hoping that we find that silver bullet in an insect,\u201d said Lambert. \u201cBut in the meantime, we still are deferring to the sort of traditional, high intensity methods of removing Arundo in the river.\u201d<\/p>\n But those methods\u2014the mechanical and chemical approach developed by Vartanian and others more than 30 years ago\u2014remain mired in the same dysfunction they always have. On the Santa Clara River, where Dudley and Lambert focus much of their research, no organization, agency, or individual has emerged to direct a coordinated Arundo removal campaign. Although some work has taken place, Arundo control in that watershed has mostly been small-scale, scattershot, and ultimately ineffective, hindered in no small part by the river flowing through two counties and countless private landholdings. \u201cToo many cooks in the kitchen,\u201d said Jason Giessow, the Arundo removal consultant. \u201cIt\u2019s sad, I mean really, ultimately, the river and the habitat are paying the price.\u201d<\/p>\n A few miles to the north of the Santa Clara River, however, a different watershed seems to be offering a glimmer of hope. The Ventura River, much smaller and far less complex, has managed to make progress on a whole-watershed, top-down Arundo removal strategy. Led by the Ojai Valley Land Conservancy and bolstered by a multimillion-dollar grant from the California Department of Forestry and Fire Protection, the Ventura River is on the cusp of securing permits that would allow work year-round in the entire watershed\u2014as opposed to individual parts of it. The approach, part of California\u2019s \u201ccutting the green tape\u201d initiative, is a \u201cfirst of its kind,\u201d according to Tom Maloney, the OVLC\u2019s executive director.<\/p>\n Early one morning in September, a group of young scientists working on the project descended into the Ventura riverbottom. In one section of the channel where Arundo removal had taken place previously, the team set to work counting and classifying native species that had returned to the area. \u201cThere\u2019s so much life in this section, you can just feel it,\u201d said Martin Schenker, OVLC\u2019s restoration field manager. Farther down the riverbed, in an area that had not been treated, a solid wall of Arundo reached from one bank to the other. \u201cYou go in there and it\u2019s just stagnant,\u201d said Schenker.<\/p>\n The team hopes that the cleared area is a vision of the future. With the permitting process nearing completion, Arundo removal has already begun, with 36 acres cleared so far. And though he is eager to see it gone, Schenker concedes a certain grudging esteem for the plant. \u201cAs much as I hate Arundo, it always impresses me,\u201d he said. \u201cIts vigor and its willingness to live, you got to give it the respect it deserves. You know, it\u2019s not it\u2019s fault it\u2019s here. So admire it where it is. And then remove it.\u201d<\/p>\n In Texas,\u00a0<\/span>when Cy Tongate joined what was then called the Rio Grande Carrizo Cane Eradication Program in 2019, the effort was already struggling. The program had been created in 2015 to \u201chelp meet the Governor\u2019s border security priorities,\u201d according to its website, but it was left mostly unfunded until 2017, when it began receiving $1.5 million per year. Administration of the program fell to the Texas State Soil and Water Conservation Board, which in turn delegated most of the field work to the Pecan Bayou Soil and Water Conservation District, located hundreds of miles away from the Rio Grande itself\u2014\u201cnobody else wanted to do it,\u201d said Tongate. Fresh out of college, Tongate was excited for the challenge, viewing it as \u201can opportunity for us to kind of take some big swings.\u201d<\/p>\n The bureaucratic headaches began at once. The Department of Public Safety had urged the program to focus on certain \u201cpriority areas,\u201d but the majority of those sites were located on land owned by the US Fish and Wildlife Service. When Tongate and his supervisor met with USFWS officials, it was a disaster. The officials said that for any work to take place on their land, the program would have to conduct an environmental impact assessment. The cost was estimated to be between $5 million and $10 million, many times the annual budget of the entire program. The officials also expressed concerns about the program\u2019s herbicide, Imazapyr, though it turned out, according to Tongate, they themselves also used the chemical. \u201cIt was pretty clear it was more of a turf fight than actual concern,\u201d Tongate said.<\/p>\n At Amistad National Recreation Area, near Del Rio, officials expressed interest in allowing the program to work on their land, but by the time a formal proposal was put together by officials at Amistad, Tongate\u2019s program had run out of funding for the year. When the new fiscal year began, the proposal had expired and the official who had spearheaded it had retired. The effort collapsed.<\/p>\n In Big Bend National Park, Tongate and his colleagues managed to establish a memorandum of understanding with park officials, an encouraging first step toward treating Arundo there. But when Tongate sent the document to superiors at his own agency, they refused to sign, unsure whether state agencies could enter into MOUs with federal agencies. The MOU was kicked to the attorney general for input, kicked back to Tongate\u2019s team for revisions, re-submitted to the National Park Service to approve the revisions, and finally, after many months, signed. But that was just a memorandum of understanding\u2014any formal plans to do work would have to undergo their own byzantine approval processes. \u201cA lot of Texans would be offended to think that their bureaucracy is as slow and incompetent as California\u2019s,\u201d Tongate said. \u201cBut it is.\u201d<\/p>\n When the work did manage to proceed, it encountered difficulties. Spraying herbicide from helicopters, which until 2022 was the program\u2019s favored approach, did not seem to achieve the desired results. An assessment conducted by the US Geological Survey in collaboration with the carrizo cane program in 2020 and 2021 found that the aerial spraying only reduced the plant\u2019s coverage by 14 percent, far from the 85 percent reduction stipulated in the program\u2019s request for proposals\u2014the job description that contractors bid on. To make matters worse, the work could also be dangerous. <\/p>\n Once, while one of Tongate\u2019s contractors was surveying Fronton Island, a large landmass in the Rio Grande used by cartels, border officials came upon an unexploded hand grenade in an abandoned backpack. Another time, a contractor applying herbicide from his boat came under fire, an unseen gunman spraying dozens of rounds into the side of his aluminum boat. \u201cThe contractor after the incident told us that he wasn\u2019t going to come back until he had built an armored boat,\u201d said Tongate. \u201cHe never did come back.\u201d<\/p>\n Following the failure of the helicopter spraying, the program shifted its focus to drones. The drones, Tongate said, could get lower, penetrating the Arundo canopy and achieving better coverage with the herbicide. Although a formal assessment hasn\u2019t been conducted, Tongate said that the drone method appears to be achieving a much higher rate of reduction, knocking back the thick monocultural stands like the ones near Shelby Park. But early on, the drone work encountered a problem of its own.<\/p>\n![\"A](\"https:\/\/www.motherjones.com\/wp-content\/uploads\/2026\/03\/Photo1.jpg\")
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