The least complex and most effective devices were designed to gather and poison or bag the young locusts. The Adams, Anderson, and Canfield Pans all depended on dragging a flat pan (ten to fifteen feet wide and two or three feet deep) filled with kerosene or coated with coal tar through an infested field. Panicked locusts hopped over the low lip at the leading edge of the pan and perished in the oil or gunk. The simplest of all these devices came to be known at the Robbins Hopperdozer. This was essentially a modified road scraper with the interior coated in coal-tar.2
In 1877, Minnesota subsidized the purchase and distribution of 56,000 pounds of sheet iron and 3,000 barrels of coal tar for arming the farmers with hopperdozers. The community of Litchfield alone claimed that more than a thousand of these contrivances were in use that year, each collecting 2 to 5 bushels of locusts a day. Later reports placed locust harvest at 200 pounds per hour, or more than 2,500 individuals per minute.
The Benson, Godard, Hutchins, Sylvester, and Wilson-Rhode Locust-Catchers were a bit more varied than the poisoned pans, the former netting, scooping, sweeping, or otherwise depositing locusts in a collection bin to which a removable bag or box was attached. These inventions did away with the problem of disposing of locust-laden kerosene or tar, but they created the problem of burying or otherwise destroying bushels of nymphs. For these locust-catching devices, the best marketing award has to go to John Carlen of Bernadotte, Minnesota, who appears to have been the only inventor clever enough not to name his machine after himself. That said, there is no evidence that Mr. Carlen’s “Hero ’Hopper-catcher” caught more than its share of locusts or sales.
An editorial in the St. Paul Pioneer Press suggested that the hopperdozer provided “complete efficacy in clearing the land of hoppers [and that] pluck and perseverance meet with their just reward in the saving of their crops by those who exercise it.” Such enthusiasm surely boosted the spirits of the struggling farmers. Even if your team is getting trounced, it’s still nice to have cheerleaders shouting encouragement. However, Minnesota historian Annette Atkins was probably right in claiming that the real value of inventing, adapting, refining, and using these machines was psychological. The smashing, scooping, and sucking provided the settlers with a sense of doing something, of not being helpless. Through their labor they affirmed the work ethic and honored rural values. But despite the newfangled inventions’ having been of limited use in controlling locusts, modifying standard agricultural practices had substantial promise.
FLOODS, FURROWS, AND FARMS
The eggs left behind by the swarms were the one life stage against which the settlers could readily launch a counterattack. These buried pods were highly concentrated, so less labor could yield greater results than trying to battle nymphs or adults. And most obvious and important, the eggs were immobile, unable to evade whatever punishments humans devised. In this regard, the keys were to alter the amount of water and disturb the protective cover of soil.
Females preferred to oviposit in well-drained sandy soil, so the eggs were normally kept dry by virtue of their parents’ having carefully chosen a suitable nursery. Although the locusts’ eggs were well protected from natural assaults, prolonged and repeated flooding could eventually drown the embryos. With irrigation, the farmers could inundate their fields in the fall or, more commonly, in the spring before the eggs hatched. With good luck and timing, an observant settler could even flood the fields just as the tiny nymphs were emerging from the soil.
Likewise, the buried eggs had no defense against an assault by the plow and harrow. The plow was used to turn the soil and bury the eggs deep in the earth so that the nymphs could not wriggle to the surface. Conversely, the harrow raked the eggs to the surface, exposing them to the elements and hungry scavengers. However, as if suspecting such a counterattack on their offspring, locusts often foiled these strategies by destroying the forage and grain prior to laying their eggs and moving on. This lack of feed translated into a severe shortage of draft animals, and finding horses, mules, or oxen to plow or harrow the infested fields was nearly impossible in many cases. There was one last, spectacularly desperate means of disrupting the soil that harbored the next generation of locusts. A few farmers resorted to dynamiting the egg beds, which surely did far more good to their sense of vengeance than it did harm to the locusts.
Once the nymphs hatched, hand-dug ditches made effective pitfall traps for the little locusts. In this inverted version of trench warfare, the open fields were safe but the trenches were deadly. Trial-and-error revealed the optimal ditch dimensions: eighteen inches wide and two feet deep—too wide for the nymphs to hop across and too deep for them to escape. The depth could be reduced if there was a means of filling the bottom of the trench with water. Conversely, some farmers dug the trenches extra deep so that the trapped insects could be buried once the stench of their decay became overpowering, and the ditch would continue to function. Otherwise, the moldering bodies had to be shoveled out or new trenches had to be dug. In general, the bands of nymphs were simply allowed to wander into the ditches of their own accord, as they seemed to have no hesitancy in tumbling over the edge. Impatient farmers attempted to drive the bands toward the lethal pitfalls using flails, but this was rarely necessary or worth the effort. In at least some cases, the trenches were spectacularly successful. According to the Nebraska Eagle: Farmers living at Brushy Bend dug a ditch over half a mile long, on the north side of a farm. At the bottom of the trench they made holes about five feet apart, making about four hundred and eighty holes in all. Each of these holes will hold about a bushel, and the ’hoppers traveling south from the sand-ridges will fill them quite full in one day. This would seem incredible, but nevertheless that one ditch is destroying about four hundred and eighty bushels of hoppers per day.
As the swarms continued to plague the settlers, farming practices began to change. The swarms provided some benefits to those people who had the ability to financially absorb the immediate losses. Although most homesteaders relied on hand-to-mouth subsistence, established farmers found that replanting crops with late fall yields could offset some of their losses. One Missourian optimistically noted that after the swarms departed in July, “Root crops do well, and vegetables of all kinds attain immense proportions, owing to the freedom from weeds, and fertility resulting from the dung and bodies of the dead locusts.” But the locusts caused much broader and more profound changes in agriculture than such tactical shifts suggest.
Historians credit the repeated invasions by the locusts with reshaping American agriculture west of the Mississippi River into the production patterns that persist today. Admonished by federal entomologists, farmers began to diversify their production systems. Wheat had come to nearly monopolize the Midwest, but this crop was particularly vulnerable to the locusts. For example, nearly two-thirds of the Minnesota farmland was producing wheat in 1873, just before the locusts’ most withering offensive. By the last year of the invasions, less than one-sixth of the land was in wheat. The farmers learned that peas and beans were far less vulnerable to the insects, and corn was a more robust grain crop than wheat.3
In addition to planting alternative crops, many farmers turned to animal production. Poultry could exploit the locusts to some degree, but the greater shift was to dairy and beef. Although pastures were often damaged by the locusts, these lands were almost always left in better shape than the crops. In particular, native grasses and rangelands seemed to fare relatively well or at least to recover rather quickly after a swarm departed. Farming the semiarid lands west of the 100th meridian was a marginal venture without the locusts, and these insects were the nail in the coffin for many homesteaders. Ranching, however, relied on the native grasslands. And cattle production became the mainstay of western agriculture. The prairies could be, and frequently were, overgrazed by livestock, but they were often mercifully passed over by the swarms migrating to more fruitful and verdant lands.
This approach to battling the locust really amounted to conflict av
oidance, rather than direct confrontation. As with flooding, plowing, harrowing, and ditching, diversification required no technological sophistication and little capital investment. All of these practices had been available to farmers for centuries. But wasn’t America the land of innovation and industry? Where were the chemical and biological weapons that dominate the modern agricultural battlefield?
POISONS, PARASITES, AND PREDATORS
Insecticide chemistry was in its infancy during the Rocky Mountain locust’s heyday. Some of the machines invented to assault the insects made use of poisons, such as kerosene, coal tar, and sulfur fumes, but these were incidental to the function of the machine. Any of these lethal substances could be, and were, replaced with devices to crush, bag, or incinerate the locusts. However, various and assorted chemicals were directly applied to the locusts or the plants they were consuming. Salt, saltpeter (potassium nitrate), naphthalene (the active ingredient in mothballs), kerosene, and cresylic acid soap (derived from coal tar) provided little control, and some of these chemicals probably killed more crops than locusts. Plant extracts, such as pyrethrum powder and quassia water, worked no better, but at least these remedies were safer for people and plants. Milo Andrus, a creative but apparently unorthodox Mormon farmer, suggested sprinkling whisky on locust-infested plants. Perhaps this was Milo’s way of disposing of a forbidden liquid, but the whisky would have been more effective in drowning his sorrows than in intoxicating locusts.
The most effective insecticides of the day were arsenical compounds—lead and calcium arsenate. These poisons were usually mixed with bran to create an oatmeal-like paste that was applied to the bases of trees or scattered through an infested field. Although there were no reported cases of human poisonings, dead birds were often seen in the treated fields. Rabbits and hares seemed to fare the worst of all creatures. And whereas large numbers of vertebrates were killed by the deadly bait, only a small proportion of the pests were poisoned.
The greatest limitation to waging effective chemical warfare against the locusts was operational. There was simply no way to effectively disperse the insecticides on the necessary spatial scale. Shoveling globs of poisoned mash was a terribly inadequate means of application. Chemical control was logistically impossible without insecticides formulated as liquids or dusts, equipment to deliver the poison efficiently, and vehicles to efficiently move the sprayers through the fields.
An entomologist of the time concluded, “There is yet room here for experiment, though, considering that in all historical times, the resources of many nations have been employed against Locusts without furnishing anything that will protect plants on a large scale—little hope can be entertained of discovering such a substance,” and he was right for nearly seventy years. The widespread use of synthetic organic insecticides came with the popularization of DDT in the 1940s, after which a flood of pesticides poured into American agriculture. The 1960s might have risked becoming the era of silent springs, but the 1860s seethed with the whirling cacophony of locust swarms.
The settlers were well aware that natural enemies often thinned the ranks of the locusts. The farmers saw an array of predators and parasites consuming their foe, most often witnessing legions of scarlet mites and swarms of buzzing flies emerging from the fallen locusts. In some cases, they drew erroneous but understandable conclusions regarding their most potent allies. In 1878 and 1879, astute Mormon farmers noticed that the locusts were dying in a most unusual and dramatic manner: “Brother John Dayes, of the 20th Ward, called this morning with a number of pests that had clustered together on the sprig of a currant bush, and were holding each other with a death grip. They were mere shells, the whole internal portion of their bodies having been gnawed away by an insect, which bores its way through the ironclad, outer covering and never leaves its prey until death ensues.”
They had observed a fungal epidemic, not the work of an insect parasite. This malady is now known as summit disease, so named for the propensity of the locusts or grasshoppers to climb to the top of vegetation in the terminal stage of infection. But our understanding of microbial pathogens in humans, let alone insects, had barely dawned in the 1870s. The germ theory of disease had been advanced less than a decade earlier by Louis Pasteur, and Robert Koch’s first proof of bacteria causing disease (anthrax) did not come until 1876. So it is not surprising that the people of the frontier waged biological warfare against locusts using livestock rather than microbes.
The settlers found that chickens and turkeys could be used to protect gardens from some of the depredations of the locusts, although a full-fledged swarm quickly overwhelmed the domestic fowl. Moreover, tainted meat and lethally overstuffed birds were potential costs of turning the poultry loose on the locusts. After the swarms had moved on, cattle were herded into fields to stomp the buried eggs of the locusts. This pummeling proved quite effective if the soil was moist or friable, but only so much land could be trampled. Even pigs were pressed into service, as they proved to be nearly as enthusiastic about locust eggs as they are about truffles. The hogs happily rooted through the soil to scavenge the delectable egg pods. Again, however, there were not enough pigs in the nation to turn the tide of locusts.
The most potent allies of the farmers were the native birds, many of which reportedly consumed vast numbers of locusts. Indeed, birds were hailed as such effective forces in the battle against the locusts that several states revised game statutes and passed legislation to protect these locust predators. Such laws were necessary in light of the enormous numbers of birds that were being hunted. Although precise numbers are difficult to determine on a national or regional basis, local statistics provide a powerful impression. The records from Bohannon Brothers, a butchering firm in Nebraska, show that the ten meat packers in Lincoln shipped out 50,000 prairie chickens and quail in 1874 and 1875. In eastern Nebraska, Johnson County estimated that 10,000 prairie chickens were exported each year, and neighboring Pawnee County reported twice as many of these birds shipped in 1874. The September 8, 1865, edition of the Omaha Republican reported, “On the 6th Captain Hoagland’s party bagged 422 prairie-chickens, 4 quails, 6 hawks, 1 duck, 4 snipe, and 1 rabbit; total, 462. Captain Kennedy’s party bagged 287 prairie-chickens, 2 quails, 8 hawks, 15 ducks, 6 snipe, and one rabbit; total 353. Excluding the two rabbits, the total number for one day by these two parties was 813 birds.”
Across thirty counties in Nebraska, the average number of prairie chickens and quail destroyed each year was placed at nearly half a million. By one estimate, these avian allies would have consumed 486 trillion insects—had the birds been allowed to live. And, of course, the number would be truly astronomical if extrapolated across the western states. But there was good reason that the calculations came out of Nebraska, for this state produced one of the most audacious characters in the story of the Rocky Mountain locust.
Professor Samuel Aughey, Jr., provided the reports that transformed our ecological and legal perspectives concerning the role of birds in suppressing insect outbreaks—and in stemming the flood of locusts across the West. His data were revolutionary, his numbers were startling, and his extrapolations were courageous. Although nobody doubted Aughey’s powers of persuasion, his scientific integrity was another matter. This first director of the University of Nebraska State Museum was hailed as a scientific pioneer by some and disparaged as a charlatan by others. Aughey’s story reveals a great deal about the lives and times of nineteenth-century scientists in America—revelations that reverberate throughout the tale of the Rocky Mountain locust.
Born in 1832, Aughey grew up in simple conditions in rural Pennsylvania. Through childhood collecting of fossils and Indian artifacts, he became fascinated with natural history. After teaching school for a time, Aughey entered Pennsylvania College, graduating in 1856. Following an itinerant period of teaching and surveying, he entered the Lutheran Theological Seminary in Gettysburg and was ordained in 1858. He married Elizabeth Catherine Welty that year and shortly thereafter accepted a cal
l to serve a church in Lionville, Pennsylvania. Much to his delight, the position allowed him to maintain his dual interests in science and theology. These two passions might have been sustainable, but Aughey was a man of many, sometimes conflicting, desires, which variously proved to be his undoing throughout life.
In this case, he desired to be both a rural minister and a social activist. Aughey apparently adored the public limelight—which was not a quality that sat well with a small Lutheran community. His outspoken abolitionist views put him at odds with members of his congregation, and he resigned after four tumultuous years. He served a few other Pennsylvania churches and then landed a position as an army chaplain. According to the Aughey family story, he was a secret agent for Abraham Lincoln, although there appears to be no substantiating historical evidence of his adventurous role in the Union forces. Indeed, Aughey seemed remarkably adept at inflating his accomplishments. His daughter recounted that her father had been a perilous adventurer and the first explorer of the Niobrara River and the Dakota Badlands—neither claim appears to have any basis in fact.
In 1864, he was called to a congregation in Dakota City, Nebraska, but Aughey could not settle into his pastoral role. Compelled by his childhood love of natural history, he left the ministry to devote himself to science, including the study of evolution. The family history suggests that he worked for the Smithsonian, although once again there are no corroborating records. Whether by his self-aggrandizement or his serendipitous combination of credentials, Aughey managed to convince the University of Nebraska to hire him as a professor of natural science. Religious orthodoxy was the primary requirement of faculty at the two-year-old university. Aughey could legitimately point to his theological training, his orthodoxy being rather dubitable in light of his liberal politics and advocacy of Darwinism. But in 1871, there could not have been an abundance of ordained ministers with aptitude in the natural sciences on the Nebraska frontier.
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