Introduced to North America in the 1860s the Cypress Spurge (Euphorbia cyparissius) is a plant that has invaded many open farmlands but is toxic for horses and cows to ingest. In 1994 Don and Heather Minto from the Society for the Preservation of New England Antiquities (SPNEA) introduced insects onto SPNEA property to control Cypress Spurge. The University of Rhode Island introduced a total of six insects that can be used as biocontrol agents for Cypress Spurge. Five of the insects are Chrysomelid beetles in the genus Aphthona and one is a a Cecidomyiid fly gall midge, Spurgia esula. They were released in batches of 500-2000 at nine sites throughout Rhode Island. The two most successful species were A. nigriscutis and A. flava which successfully reproduced and decreased the amount of Cypress Spurge at the release sites.