An Account of the Insects Noxious to Agriculture and Plants in New Zealand: The Scale Insects (Coccididae)

In Short

Commissioned by New Zealand's State Forests and Agricultural Department, this 1887 handbook provides the first comprehensive survey of the country’s scale-insect species. It breaks down their anatomy, life cycles, and secretions, evaluates common agricultural remedies, and offers a systematic catalogue to help growers identify and eradicate infestations. Blending field observation with rigorous entomological taxonomy, it bridges academic science and practical horticulture. Its historical value endures as a founding text of New Zealand economic entomology, documenting both native fauna and early invasive threats.

The Story

The text begins by setting out an urgent agricultural problem: New Zealand’s mild, humid climate allows scale insects to thrive on both native plants and introduced crops. Because these pests draw their sustenance by inserting a rostrum beneath the surface of leaves and bark to suck plant juices, surface-level contact poisons prove entirely ineffective. To combat them, landowners cannot rely on guesswork; they must learn to recognize the subtle physical traits and life stages of each pest.

The author opens with a essential primer on Coccididae, tracing their name back to the ancient Greek kokkos—the source of a rich red dye—and detailing their economic history from cochineal to modern synthetic aniline dyes. From there, the book walks through the four life stages of scale insects: egg, larva, pupa, and adult. It highlights the stark dimorphism between the sexes. Females often degenerate into immobile, sac-like forms buried under protective waxy or cottony shields, while the short-lived males emerge as delicate, winged flies.

Beyond direct physical damage, the author tracks the secondary nuisance of scale infestations: the excretion of sticky "honeydew," which invites a black, smothering fungus known as "smut" or "black blight." Natural checks, such as predatory birds or parasitic wasps, are often absent or insufficient for aggressive species in New Zealand.

The narrative shifts to practical application, evaluating twenty-two popular remedies. The author disproves widespread horticultural myths—dismissing sulphur, soot, pyrethrum, and salt as useless against scale insects—while warning against hazardous treatments like sulphuric acid, caustic soda, or lime mixtures that kill the host tree without harming insect eggs. Instead, kerosene emulsions and hot soap solutions emerge as the only reliably effective measures.

The extensive final section forms the core diagnostic catalogue. The author systematically classifies New Zealand's Coccidae into subfamilies, genera, and species, detailing physical dimensions, antenna joint counts, spinneret patterns, and host plants. The work concludes with grave warnings regarding invasive species, particularly Icerya purchasi (the cottony-cushion scale), urging growers to burn infested trees immediately to prevent agricultural ruin.

How It Unfolds

The problem defined The introduction establishes the severe threat scale insects pose to New Zealand's forests and gardens, noting that existing scientific literature is scattered and inaccessible to practical growers.

Anatomy and life cycles The text examines the metamorphoses of male and female Coccids, explaining how females construct protective waxy tests while males undergo pupation to emerge as short-lived winged flies.

Products and secondary blights The book describes how feeding Coccids produce honeydew, which rapidly leads to dark fungoid growths that choke foliage and hide active colonies.

Debunking popular remedies The author systematically tests twenty-two proposed chemical and natural cures, exposing common misconceptions—such as stuffing tree trunks with sulphur—and recommending simple soap and kerosene treatments.

The systematic catalog The text moves through detailed species diagnoses across multiple groups, carefully recording body measurements, antenna structures, and host plant associations.

Alerts on invasive pests The concluding pages single out destructive introduced species like Aspidiotus aurantii and Icerya purchasi, warning of their potential to destroy New Zealand's citrus industry.

The People

William Miles Maskell The author and main authority of the text. He wants to synthesize scattered scientific research into a accessible handbook for farmers and naturalists. Driven by meticulous observation, he scrutinizes microscopic anatomical details, debunks ineffective traditional remedies, and advocates for rigorous insect management.

John Ballance The Commissioner of State Forests, under whose official instructions the work is prepared and published. He seeks to protect the colony's agricultural economy and forestry resources from devastating insect blights by funding practical scientific literature.

European and American Entomologists (Comstock, Hubbard, Signoret) Distinguished overseas researchers whose experimental findings Maskell regularly cites and compares against New Zealand species. They represent the broader international scientific effort to understand and control agricultural pests.

New Zealand Fruit-Growers and Gardeners The intended audience of practical land managers. They face financial ruin from crop loss and often resort to ineffective, superstitious remedies like stuffing sulphur into tree trunks. The book aims to transform them into informed observers capable of identifying specific pests.

In Its Own Voice

"The number and variety of the insect pests which live on the plants of New Zealand, whether native or introduced, and the damage which they frequently do, form the excuse for the appearance of this work."

"Sulphur. Another substance, the object of a kind of superstitious veneration amongst gardeners. It is excellent against fungoid growth, but of little value against scale-insects."

"Orange- and lemon-growers in the north of New Zealand should beware of this pest. It is scarcely likely that it should be harmless here when it is so destructive elsewhere."

What It's Really About

The work addresses the urgent intersection of economic survival and scientific classification in a colonial ecosystem. At its core, the text argues that effective agricultural management requires precise, evidence-based taxonomy rather than traditional folklore or untested chemical remedies. Maskell stresses that one cannot combat a pest without understanding its physiological mechanisms, such as how it feeds beneath the plant surface or how its waxy shield protects it from weather and predators.

The book also highlights the ecological vulnerability of New Zealand's native flora to imported agricultural pests. It presents an early argument for strict biosecurity, showing how human commerce inadvertently transfers destructive species across international borders, threatening both native wilderness and domestic agriculture.

Why Read It Today

This volume appeals to historians of science, botanists, and natural history enthusiasts interested in 19th-century scientific literature. It offers a clear window into early colonial naturalism and the birth of economic entomology in the Southern Hemisphere. Maskell’s writing is surprisingly direct, crisp, and accessible, completely free of needless jargon or posturing.

Modern readers will appreciate the author's sharp, dry wit when debunking popular horticultural remedies. He treats the reader as a fellow observer, guiding the eye through microscopic details—from the jointed antennae of male flies to the air-cells of waxy shields—with patient clarity.

The primary difficulty for contemporary readers lies in its dense, highly technical taxonomic catalogues, filled with anatomical terminology, structural measurements, and 19th-century Latin nomenclature. Yet beneath these technical lists lies a fascinating record of environmental history. It documents the early ecological shifts in New Zealand as native plants met introduced species, leaving a lasting impression of the quiet, constant struggle between human agriculture and the microscopic world.