Tom A. Royer

Document Type

Thesis - Open Access

Award Date


Degree Name

Master of Science (MS)

Department / School



Cultivated sunflowers (Helianthus annuus L.) are an increasingly important cash crop in the agricultural economy of South Dakota. Sunflower hectarage increased in South Dakota from an estimated 59,711 ha. In 1975 to approximately 250,900 ha. In 1982 (Anonymous, 1982). Most of the sunflowers are grown in the eastern half of South Dakota, and a large percentage is growing the northeastern quarter of the state (Figure 1). The expanding hectarage has necessitated an increase in insecticide application to control the several insect pests associated with them. It is estimated that 181,900 ha. Were treated with insecticides in 1982 (D. Walgenbach, South Dakota State University, Personal Communication). The objectives of this study were (1) to investigate the potential for using artificial infestations of sunflowers, (2) to collect and identify entomophagous arthropods associated with sunflowers, (3) to investigate the seasonal abundance of the most common predators, and (4) to study the potential predator-prey relationships between the most common predators and the sunflower moth larvae.

Library of Congress Subject Headings


Sunflower -- Diseases and pests

Sunflower -- Diseases and pests -- South Dakota



Number of Pages



South Dakota State University