By Blake Jackson
Cornell University researchers are urging New York soybean growers to closely monitor fields for white mold, a disease that is increasingly being reported across the state.
According to Anas Ashfaq, Undergraduate Research Assistant, and Camilo H. Parada Rojas, Field Crops Pathologist, Cornell University, recent confirmations of white mold in several regions indicate that conditions are favorable for disease development and that timely management is critical.
The disease was confirmed in a soybean field near Macedon, New York, on August 11, 2026, and additional cases have been reported in St. Lawrence County and eastern New York.
Growers are encouraged to inspect fields, particularly those with a history of white mold, and determine whether crops are within the key management window between the R1 (beginning bloom) and R3 (beginning pod) growth stages.
White mold is commonly identified by white, cotton-like fungal growth on stems, branches, and pods. Symptoms typically become visible between the R3 and R6 growth stages.
As the disease progresses, it produces hard black structures called sclerotia, which allow the pathogen to survive in fields for years. Infected plants often display wilted, brown leaves that remain attached to the stem.
Researchers emphasize that managing white mold requires an integrated approach that combines resistant varieties, proper seeding rates, row spacing decisions, and timely fungicide applications.
Fungicides are most effective when applied preventively during flowering, generally between the R1 and R3 stages. Applications made after symptoms appear are usually less effective.
Growers should consult current soybean fungicide efficacy recommendations and use only products labeled for white mold control in New York. They should also follow all label requirements regarding application timing and rates.
Because white mold can persist in fields for multiple seasons, documenting affected areas is important for future management planning.
Cornell University's Field Crops Pathology Lab is also seeking soybean fields with severe white mold infestations to support ongoing research aimed at improving long-term disease management strategies.
Growers who suspect significant infections are encouraged to contact their local Extension office or Cornell specialists for assistance and field evaluation.
Photo Credit: gettyimages-gilaxia
Categories: New York, Crops, Soybeans, Education