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A potential Phomopsis infection period observed

At Winchester, the rain started around 10:40 am Tuesday, and although it stopped during the night, the relative humidity stayed high (>90%) until 9:20 am today.  During this wet time, the average temperature was around 47F.  This is a borderline case for Phomopsis infection.  If you did not have issues with Phomopsis in the past, the risk was probably close to none.  If you had seem a lots of Phomopsis in recent years, you may have some infection, depends on the temperature you observed during the rain.  If it was mid to low 40's the fungus has a difficulty infecting tissues.  If it is more around 50F, 17 hours of wet period will results in moderate level of infection (15-25% severity with a very strong presence of spores).

We (northern VA) may have thunderstorm in this Friday, the rest of the state seems to have several sunny days.  Please check your local weather forecast.
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