Pharaoh Had It Easy


A United States government entomologist, Charles V. Riley, who was very much on the scene during the critical years of infestation, industriously gathered all available data on the grasshoppers’ behavior and issued bulletins as to effective countermeasures.

“When the insects are famishing, it is useless to try and protect plants by any application whatever,” he wrote resignedly, “though spraying them with a mixture of kerosene and warm water is the best protection we have tried.” Riley instructed the fruit farmers to whitewash the trunks of their trees; the lime flaked off as the creatures tried to claw their way into the foliage, depriving them of a foothold. The whitewash applications had to be repeated frequently, and Riley tacitly acknowledged the partial ineffectiveness of this strategy by recommending that the farmer shake his young trees vigorously from time to time.

Experiments proved that locusts on the march might be blocked and destroyed in great numbers by digging in their path ditches two feet wide and two feet deep. The majority stumbled blindly into these traps and could mangle each other fatally in their mad struggles to get out again. It was further found that they could be channelled into death pits by arrangements of converging strips of netting or muslin. These devices were not geared, however, to exterminate locust armies advancing on a one-mile front, which often happened.

All this while, to be sure, inventive-minded individuals were deep in designs for machinery to combat the scourge. In general, the contraptions that emerged from the workshops and smithies were known as “hopper-catchers” or “hopperdozers”; some actually worked.

Usually horse-propelled, the hopperdozers attained widths of up to forty feet. The principles of operation varied. The Flory Locust Machine, for example, sought to crush the locusts between two rollers. Several horsedrawn scorching-machines were produced. The King Suction Machine was built on the vacuum-cleaner concept, with eight-inch tubes, flattened at the mouth, running close to the ground and drawing the pests into a chamber where a large fan rotated at twelve hundred revolutions per minute, providing the necessary air flow and effectively pulverizing the grasshoppers.

The glaring weakness of these designs was the assumption by their creators that most locust-ridden farmland was as smooth and level as a village green. On rough, sloping ground the machines were as helpless as a full-rigged ship in a creek bed.

Many farmers put their trust in machines that plunged the grasshoppers into a bath of water and coal oil. Equipped with a projecting unit called a “disturber,” which impelled the quarry to leap into the air, these machines were supposed to catch the insects against a wire screen and deflect them into the pan filled with the oil-and-water mixture. Advocates of this method were aware that many of the insects scrambled out of the pan, but were comforted by the belief (it turned out to be unfounded) that a brief exposure to the fluid would be fatal.

The development of such fearsome contrivances and others like them probably does not explain the virtual absence of Melanoplus spretus when the spring of 1878 arrived. Many factors may have caused its disappearance: the weather the year before had not been favorable for breeding; parasites that preyed on the grasshoppers and their eggs had multiplied; and it was noted repeatedly that the locusts of the summer of 1877 had been sluggish and, as the farmers phrased it, “used up.”

In August, 1876, the Georgetown, Colorado, Miner carried a dispatch illustrating the susceptibility of the locusts to atmospheric turbulence and sudden temperature change: “As the ravenous millions were driven up against the high ranges about Mount Evans, they were chilled and commenced falling into the little stream that flows near Sisty’s place, until for days, the rivulet was transformed from a sparkling stream of limpid water into a floating mass of dead grasshoppers, the water becoming so corrupt and offensive that neither man nor beast could tolerate it. The trout pond in Mr. Sisty’s meadow became so putrid that he was compelled to cut away the dam and let the accumulated filth flow off.”

Uncounted millions of Rocky Mountain locusts died in the snows of upper Yellowstone Park. They may be seen today, by those intrepid enough to survive the trip by jeep, horseback, and foot to the Grasshopper Glacier. In layer upon layer, the insects lie in this 11,000-foot-high deep-freeze. It is impossible to pinpoint the exact years in which they died there, but scientific tests have established that these grasshopper deposits very possibly coincided with the great plague, the victims chilled in flight like those that fell on Mr. Sisty’s farm.