Parasites and Predators in Paradise: Biological Control and Species Introduction in Early 20th-Century California

At the turn of the 20th century, the scientific method of biological control came to its time in the United States, with the agricultural landscape of California being its crucial site of experiments and practice. Its practitioners, the entomologists who worked for the U.S. Department of Agriculture, the state government, and the universities in California, made great efforts to find a cure for hordes of alien pests that threatened to destroy economic crops through the introduction of the pests' natural enemies, their natural predators and parasites. Their first major success was saving the citrus industry from the cottony cushion scale with the introduction of the Vedalia beetle from Australia. Since then, biological control has been seen as a panacea for agricultural pests for some time, and a global network of knowledge and species exchange among entomologists was established, with institutions like the State Insectary and the University of California’s Citrus Experiment Station being its central node.

My research argues that the success of biological control was rooted in the historical context of mass species introduction in the United States. Since the beginning of the first settlements, introduced crops and domesticated animals have been a driving force of agricultural expansion in the United States. The introduction efforts became stronger than ever at the turn of the century, and the vision of an “Eden” in California was built upon the introduction of crops. It was in this climate that the idea of biological control prevailed, creating an agricultural landscape in which scientists and agricultural workers believed that the introduction of new species could protect other introduced species from the harmful species that came with them. To protect an artificial and agricultural paradise, dedicated plant explorers collected and classified insects around the world, to select a few to breed and distribute into fields and orchards.

To present this research in a visually appealing way, I plan to use a map to showcase where the introduced species were collected, pair it with historical pictures of how these insects were bred in California and how the method was advertised on journals, posters, and murals on the upper half of the poster, emphasizing the significance of introduced "beneficiary" species' key roles in the transformation and "improvement" of local landscapes in the eyes of the contemporaries. On the lower half of the poster, I will make a graph to help explain the intellectual genealogy and institutional affiliations of the key entomologists and agronomists, connecting them to the agricultural sciences shaped by practices of settler colonial agriculture, and the ecology that rose after the height of biological control. I see the insects introduced to California to protect citrus and other crops as one of the last patches of consciously and carefully introduced "creatures of empire" to the American continent to help its agricultural settlement.