We have received numerous field reports of early (late March) blueberry rust in 2016, likely as a result of a milder than average winter and the recent heavy rainfall observed in many blueberry production areas.  It is a good time to start scouting for rust if you have not already done so.  Russel Ingram, a graduate student in Plant Path at the University of Georgia, has also observed active sporulation of rust on old leaves from 2015 that have not abscised. The blueberry IPM guide at www.smallfruits.org provides information on specific fungicides for rust management.  If a variety is susceptible to rust, early defoliation can result, and this will reduce yields next year as a result.  Scouting is required to determine whether rust is developing in specific varieties.  Many fungicides applied for other leaf spots will also have rust activity; this is particularly true of the strobilurin (Abound, Pristine, etc.) and DMI fungicides (Proline, Quash, Tilt, Orbit, Indar, Bumper, etc.).  Please advise your commercial blueberry producers that they should be concerned about post-season leaf spot management, and they should consider fungicide application as needed to prevent premature defoliation due to rust, Septoria, and anthracnose leaf spots.

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