Disease management information directed mostly to the Frederick County Virginia tree fruit industry, updated as needed throughout the growing season. Keith Yoder, Virginia Tech Agricultural Research and Extension Center, Winchester, Virginia
Friday, April 16, 2010
Friday morning update
Based on today's forecast, it appears that this afternoon's wetting will result in predicted fire blight infection, as shown below, and continued wetting through the night will constitute apple scab, quince rust and cedar-apple rust infection periods with winds primarily WNW from cedar inoculum sources. This will be updated with a Maryblyt graphic later this morning. With most area orchards still near full bloom, flowers are highly susceptible to fire blight and quince rust. Winds will not be favorable for spraying tomorrow so protection of high priority blocks is important. Also, consider this a secondary scab infection period for orchards that were not properly protected for the Mar 28-29 infection period.