Flytraps and Their Operation [1921]

In Short

F. C. Bishopp’s 1921 bulletin presents a practical, clear-eyed guide to constructing and operating homemade flytraps for farms, dairies, and homes. Recognizing that trapping can only supplement the primary work of sanitation and manure management, Bishopp details how simple, low-cost materials—such as wooden barrel hoops, wire screen, and lath—can be crafted into highly efficient conical traps. He explains the differing behaviors of house flies, blowflies, and blood-sucking species, detailing specific baits for each. The text endures as a masterclass in straightforward, accessible agricultural engineering.

The Story

The manual begins by establishing the true role of the flytrap within a broader sanitation strategy. Bishopp cautions readers against relying entirely on traps to eliminate pests, insisting that destroying or chemically treating breeding sites must remain the primary line of defense. Traps serve two vital functions: intercepting flies arriving from unsanitary neighboring properties and capturing those that escape other control measures. Furthermore, trap catches act as a reliable index to judge whether a farm's overall sanitation campaign is succeeding. Bishopp urges farmers to set traps early in the spring, noting that destroying a few early insects prevents the development of millions by midsummer.

From these foundational principles, the text moves to the mechanics of capture. Bishopp categorizes common house pests into vegetable-matter breeders like the house fly and animal-matter breeders like the blowfly and screw-worm fly. Blood-sucking pests like stable flies rarely enter traps, but others can be gathered efficiently if their specific feeding instincts are understood. Bishopp demonstrates that all effective traps operate on a single behavioral rule: flies are lured into a cage through a wide entrance that narrows to a tiny exit, relying on the insect's natural tendency to fly upward toward the light when attempting to escape.

The core of the work details the construction of the conical hoop trap, which tests proved to be superior in catching power, durability, and low cost. Bishopp guides the reader step-by-step through building a frame from wooden barrel hoops and laths, fitting a wire mesh cylinder around it, and inserting an internal wire cone. He provides exact mathematical calculations for geometry and pattern-cutting, ensuring anyone with basic tools can build a trap for about one dollar or less using salvaged materials. Alternative designs—such as garbage-can lid traps, window-mounted traps for barns, and large manure-box traps—are also detailed to address specific farm environments.

The focus then turns to field operation and range management, particularly in the Southwest, where screw-worm flies inflict severe damage on livestock. Bishopp outlines effective baiting strategies, matching black-strap molasses, fermented sugar sirups, or milk mashes to house flies, while recommending packing-house "gut slime" or blood tankage for blowflies. He stresses proper trap maintenance: keeping shallow bait pans filled, washing containers regularly, and emptying trapped insects weekly by heat or sulfur fumigation. The guide concludes with a brief evaluation of sticky fly papers and formaldehyde-based poisoned baits, appending strict warnings regarding the safe handling of toxic chemicals around children and livestock.

How It Unfolds

Establishing the limits Bishopp opens by positioning flytraps as a secondary control measure, stressing that eliminating breeding grounds in manure and waste must always take precedence.

Understanding the target The text classifies common fly species by their breeding habits and feeding preferences, explaining why blood-sucking species avoid traps while house flies and blowflies respond predictably to specific scents.

Designing the conical hoop trap Bishopp provides explicit instructions for building an 18-inch wire cylinder using barrel hoops, laths, and a hand-cut screen cone, complete with mathematical formulas for cutting patterns.

Adapting traps to special environments The manual explores alternative designs, including window traps for livestock barns, manure-box traps that capture emerging insects, and garbage-can lid modifications.

Deploying traps on the open range Focusing on Southern livestock operations, the guide details how to mount traps on post platforms to capture destructive screw-worm flies around cattle watering areas.

Selecting and maintaining bait Bishopp contrasts sweet fermenting mixtures like black-strap molasses for house flies with slaughterhouse products like gut slime for blowflies, closing with rules for trap placement, emptying, and safety.

The People

F. C. Bishopp acts as the central guiding authority of the text, writing with the pragmatic clarity of an applied entomologist. He wants rural working people to achieve maximum pest control at minimum expense. Standing in his way are common misconceptions about pest management—namely, the tendency of farmers to rely entirely on traps while neglecting basic sanitation. Bishopp counters this with rigorous testing and clear logic, ensuring his readers understand both the mechanics of the traps and the biological habits of their prey.

E. W. Laake, D. C. Parman, and R. H. Hutchison appear as fellow researchers whose practical innovations refine trap engineering. Laake collaborates with Bishopp on extensive field tests to confirm the superior efficiency of the conical hoop frame. Parman contributes a simplified trap variant that eliminates the heavy wooden top, allowing quick assembly with fewer tools. Hutchison designs a specialized platform for trapping maggots directly from manure piles.

Prof. C. F. Hodge and Arthur Swaim represent the inventive pioneers who adapt the core cone-and-tent principles to daily farm infrastructure. Hodge designs window-box traps that catch flies entering or leaving barns, as well as traps fitted directly onto garbage lids. Swaim devises removable screen-tent frames for manure pits. Each figure shares Bishopp's single-minded goal: turning insect behavior against the pest to protect human habitations and livestock.

In Its Own Voice

"It should be borne in mind that flytrapping is only supplementary to other methods of control, most notable of which is the prevention of breeding..."

Bishopp opens his treatise by framing traps not as a cure-all, but as a secondary defense.

"The trap consists essentially of a screen cylinder with a frame made of barrel hoops, in the bottom of which is inserted a screen cone."

He describes the construction of his primary trap using simple, plainspoken mechanical terms.

"Under no condition should the sides or top of the trap be of solid material, as the elimination of light from the top or sides has been found to decrease the catch from 50 to 75 per cent."

Bishopp emphasizes how an insect's natural attraction to light governs trap efficiency.

What It's Really About

Beneath its mechanical specifications and practical diagrams, Flytraps and Their Operation is an inquiry into applied insect behavior and rural self-reliance. Bishopp approaches pest management not as a matter of brute force or heavy chemical reliance, but as an exercise in understanding natural instincts. By observing how flies react to light, draft, and scent, a farmer can construct an inescapable trap out of scrap wood and wire mesh.

The text also argues for systematic cleanliness over reactionary fixes. Traps are useful, but they only reveal how well a homestead manages its waste. Bishopp frames public health and livestock protection as community efforts, where preventing breeding in early spring protects whole townships by midsummer.

Why Read It Today

Flytraps and Their Operation appeals to modern homesteaders, woodworkers, livestock owners, and readers interested in early 20th-century agriculture. It offers a fascinating glimpse into an era when effective farming required building equipment from scratch rather than buying commercial solutions.

Reading the bulletin is a surprisingly satisfying experience. Bishopp’s prose is direct, functional, and completely devoid of modern marketing fluff. The precise construction steps, geometric pattern calculations, and practical recipes for fermenting baits give the work a hands-on, authentic character. The author expects his reader to possess basic craft skills and a willingness to work with cheap or recycled materials.

The work presents few reading difficulties, though modern readers will notice outdated terminology regarding agricultural chemicals, as well as the unvarnished reality of rural farm sanitation—including detailed descriptions of slaughterhouse byproducts like "gut slime" used for blowfly bait. What stays with the reader is Bishopp's elegant application of basic physics and biology: using wooden barrel hoops, wire screen, and the natural flight patterns of insects to solve a massive agricultural problem cleanly and cheaply.