The Department of Plant Industry was created in 1985 as a part of the Division of Regulatory and Public Service Programs. Although the name was new, the functions of the department were a continuation of the Plant Pest Regulatory Service that originated in the 1970s; functions of that body were performed in prior decades by the College of Agriculture, the Agriculture Experiment Station, and the Cooperative Extension Service. Herman B. Jackson served as head of the department, 1985-2003.

Upon its creation in 1985, the activities of the Department of Plant Industry fell into three categories: implementing the provisions of the Crop Pest Act; monitoring cooperative state and federal programs; and participating in the National Plant Pest Survey and Detection Programs. The activities associated with the Crop Pest Act included the inspection of nurseries and licensing of dealers to sell plant material; phytosanitary certification, which was the certification of plants to be exported; post-entry inspections, which was the inspection of plants arriving from outside the United States. The activities associated with monitoring cooperative state and federal programs included citrus fumigation, and tracking the spread of witchweed, gypsy moths, imported fire ants, and boll weevils. Activities associated with national detection programs included the Japanese beetle and exotic pests.