The bulletin opens by distinguishing two groups of short-tailed field mice: meadow mice (Microtus), which live chiefly in surface runways under grass or snow, and pine mice (Pitymys), which, like moles, inhabit underground burrows. This structural contrast—above versus below—shapes the entire work. Lantz notes that meadow mice are “very prolific, breeding several times a season” with litters of 6 to 10, and under favorable conditions they “sometimes produce abnormally and become a menace.” The text moves from describing these habits to cataloging control methods, including trapping, poisoning, and encouraging natural enemies.

Surface Runs and Subterranean Burrows

The bulletin’s first major division contrasts the runways of meadow mice—hollowed out under grass, leaves, weeds, brush, boards, or snow—with the entirely underground tunnels of pine mice. Lantz emphasizes that meadow mice are “mainly on the surface,” while pine mice “live almost wholly in underground burrows.” This spatial distinction governs the control strategies: surface poisons and traps for meadow mice, deeper placement for pine mice. The text also notes that pine mice can be identified by “shorter and smoother fur” and a “red-brown color,” linking physical traits to habitat. The author repeatedly ties behavior to environment, as when he observes that meadow mice build both subterranean and surface nests, suggesting flexibility in response to conditions.

Cycles of Abundance and Damage

Lantz documents that meadow mice are “widely distributed in the Northern Hemisphere” and have caused “serious losses to farmers, orchardists, and those concerned with the conservation of our forests.” He references historical plagues in the Old World and “many instances” in the United States of “extraordinary abundance with accompanying destruction of vegetation.” The language is cautious: the causes of population explosions are “not well understood,” yet the consequences are stark. The bulletin does not sensationalize; instead, it catalogs damage to crops, orchards, and forests, grounding claims in observed patterns. This section establishes the economic urgency that justifies the subsequent control recommendations.

Natural Enemies and the Role of Owls

A significant portion of the bulletin is devoted to predators, with owls receiving special attention. Lantz cites examinations by Dr. A. K. Fisher of the Biological Survey: in 1,247 barn-owl pellets from the Smithsonian Building, Fisher found 1,991 skulls of short-tailed field mice, alongside 656 house mouse skulls and 210 rat skulls. The author notes that the short-eared owl, though not abundant, “usually assemble[s] in considerable numbers” where field mice become numerous. The long-eared owl’s pellets contained 349 meadow mouse skulls out of 374 small mammals. Lantz argues that most owls are beneficial, except perhaps the great horned owl, and urges farmers to protect these birds rather than wage war on them.

Control Methods and Their Limitations

The bulletin outlines practical measures: trapping, poisoning, and habitat modification. Lantz advises placing traps in runways and using poisoned grain or apples, but he also warns that “warfare against [predators] should be limited to the minority that are more noxious than useful.” The text repeatedly returns to the idea of balance—encouraging natural enemies while selectively removing harmful ones. The author does not claim a single solution; instead, he presents a toolkit, acknowledging that “the problem of controlling the animals is one of considerable importance” and that methods must be adapted to local conditions. This pragmatic, evidence-based approach reflects the bulletin’s origins as a government publication for practical farmers.

Lantz’s bulletin remains a concise example of early 20th-century applied zoology, blending field observation with statistical evidence from stomach and pellet analyses. Readers interested in the history of pest management or the ecology of voles will find a clear, unsentimental account that prioritizes utility over narrative. The work’s value lies in its specificity: it names species, quantifies damage, and prescribes actions without overpromising results.