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    Phorid Fly

    Phorid Fly is a pest which feeds on fungi and plants and reproduces in the dark, humid environments of mushroom houses.

     

    This pest is a threat to the mushroom industry, as it destroys 10-40% of crops, contributing to increased crop losses and impacts to farm revenue. Additionally, Phorid Fly is a nuisance pest in residential homes, creating problems for local residents.

    Overview

    Effective Thursday, January 30, 2025, the Pennsylvania Department of Agriculture is implementing a mandatory treatment procedure for mushroom houses in New Garden Township and Kennett Township, Chester County due to the continued increase of Phorid Fly populations. 

    The Department, in partnership with industry, has been closely monitoring the rise in Phorid Fly populations and determined that this step is essential to safeguard our nation-leading mushroom industry. The mushroom industry in Chester County is a key part of Pennsylvania’s agricultural legacy, and it is crucial that we protect it. While many mushroom growers are already following best management practices, this action from the Department ensures that all growers are held to the same standard, helping to collectively protect and preserve the industry in Chester County.

    To assist in controlling Phorid Fly, the Department has implemented a quarantine order that will require mushroom farms in the areas and zones established in the order to perform a heat-treatment process called “steaming off” which raises the indoor temperature of the mushroom growing houses to a level sufficient to kill all flies and fly larvae. This is an established industry best management practice that has proven effective. The Plant Pest Act provides the Department authority to implement such an order and establish required treatment protocols to control, contain and limit the spread of pests and protect our agriculture industry.

     

    Call the Bureau of Plant Industry

    717-787-4843

    Email

    RA-AGPhorid@pa.gov