COMMODITY TREATMENT AND QUARANTINE ENTOMOLOGY Approved Quarantine Treatment for Hessian Fly (Diptera: Cecidomyiidae) in Large-Size Hay Bales and Hessian Fly and Cereal Leaf Beetle (Coleoptera: Chrysomelidae) Control by Bale Compression

A quarantine treatment using bale compression (32 kg/cm pressure) and phosphine fumigation (61 g/28.3 m aluminum phosphide for 7 d at 20 C) was approved to control Hessian ßy, Mayetiola destructor (Say), in large-size, polypropylene fabric-wrapped bales exported from the western states to Japan. No Hessian ßy puparia (45,366) survived to the adult stage in infested wheat, Triticum aestivum L., seedlings exposed to the treatment in a large-scale commercial test. Daily temperatures (mean SEM) inside and among bales in three test freight containers were 17.8 0.2 front top, 17.0 0.2 front bottom, 17.3 0.2 middle bale, 15.7 0.3 middle air, 18.5 0.1 back top, and 18.1 0.1 C back bottom, allowing the fumigation temperature to be established at 20 C.Mean fumigant concentrations ranged from 208 to 340 ppm during the Þrst 3 d and ranged from 328 to 461 ppm after 7 d of fumigation. Copper plate corrosion values inside the doors, and in the middle of the large-size bales in all locations indicated moderate exposure to hydrogen phosphide (PH3). PH3 residues were below the U.S. Environmental Protection Agency tolerance of 0.1 ppm in animal feeds. The researchwas approved by Japan andU.S. regulatory agencies, and regulations were implemented on 20 May 2005. Compression in large-size bale compressors resulted in 3Ð3.6 and 0% survival of Hessian ßy puparia and cereal leaf beetle,Oulemamelanopus (L.), respectively. Bale compression can be used as a single treatment for cereal leaf beetle and as a component in a systems approach for quarantine control of Hessian ßy.