Thursday, May 24, 2012

Infection period May 23-24

Last night's wetting (12 hr at 63° with 0.04 in. rain) qualified as a scab infection period. 

This wetting brought the accumulated wetting hours since Apr 18 to 234 hours. In the next couple days it is likely that we will reach the 250 wetting hour threshold for specific treatment against the sooty blotch/flyspeck fungal complex. This would be the second earliest week for reaching this predictive threshold since we began recording this in 1994. Only 2003 was earlier. This signals early summer disease pressure from the sooty blotch/flyspeck fungal complex as well as other "summer diseases" and Alternaria leaf blotch.

As expected, there are early indications of heavy brown rot pressure on ripening cherries.