Caution: The observations, conditions, and recommendations reported on this page are applicable only to the eastern counties of West Virginia. Use of the information reported here for making orchard management decisions outside of the immediate proximity of Kearneysville, West Virginia, is not our intent. Fruit producers outside the eastern West Virginia area are encouraged to consult their state extension specialists for information similar to that provided here.

	Weekly pheromone trap data and degree-day accumulations (updated every M-W-F) from WVU/Kearneysville.

• June 29, 2009
  • As of June 29, 2009, we have accumulated 293 wetting hours, for petal fall date of May 3.
• June 26-27, 2009
  • Wet for 11 hours at 65 ° F with 0.25 inches of rain. Infection period #22.
• June 22, 2009
  • As of June 22, 2009, we have accumulated 274 wetting hours, for petal fall date of May 3.
• June 20, 2009
  • Wet for 9 hours at 72 ° F with 0.01 inches of rain. Infection period #21.
• June 17 - 18, 2009
  • Wet for 26 hours at 66 ° F with 1.52 inches of rain. Infection period #20.
• June 15, 2009
  • As of June 12, 2009, we have accumulated 225 wetting hours, for petal fall date of May 3. This is the threshold value for orchards with high inoculum for sooty blotch and fly speck diseases.
• June 10 - 11, 2009
  • Wet for 15 hours at 67 ° F with 0.06 inches of rain. Infection period #19.
• June 8, 2009
  • As of June 8, 2009, we have accumulated 196 wetting hours, for petal fall date of May 3.
• June 3 - 6, 2009
  • Wet for 61 hours at 58° F with 2.21 inches of rain. Infection period #18.
• June 1, 2009
  • As of June 1, 2009, we have accumulated 131 wetting hours, for petal fall date of May 3.
• May 31, 2009
  • Wet for 7 hours at 56° F with 0.12 inches of rain. Infection period #17.
• May 28 - 29, 2009
  • Wet for 16 hours at 58° F with 0.13 inches of rain. Infection period #16.
• May 25 - 27, 2009
  • Wet for 42 hours at 56° F with 1.16 inches of rain. Infection period #15.
  • As of May 27, 2009, we have accumulated 98 wetting hours, for petal fall date of May 3.
• May 21, 2009
  • Fire blight infections are numerous at many locations. Cutting out infections early can be very beneficial for reducing secondary inoculum. Cutting early can reduce the amount of cutting by 6x compared to waiting to do it later. Read this.
  • Apple scab is easily visible in several locations.
  • First symptoms of cedar apple rust can be seen on unsprayed Golden Delicious trees.
  • The frequent wetting periods in early May have been very favorable for development of peach scab. The disease has an incubation period of six weeks, so symptoms of these infections should be visible in mid-June.
  • BASF has released supplemental labels for their products Endura and Cabrio for use on all stone fruits for control of scab, rusty spot, and brown rot. These two individual products when combined at the labeled single-use rates will provide the same amount of active ingredients as would be found in the 14.5 oz/A rate of Pristine. BASF pursued the supplemental labeling because Pristine is in short supply for 2009.
  • As of May 21, 2009, we have accumulated 56 wetting hours, for petal fall date of May 3 (2007 at this time AWH = 154, 2008 at this time AHW = 101, for petal fall dates of May 4 and May 3, respectively). Accumulated wetting hours are useful for predicting the appearance of sooty blotch on nonsprayed fruit.
• May 16 - 17, 2009
  • Wet for 14 hours at 59 ° F with 0.76 inches of rain. Infection period #14.
• May 14 - 15, 2009
  • Wet for 14 hours at 62 ° F with 0.12 inches of rain. Infection period #13.
  • Numerous scab lesions on unsprayed trees.
  • Abundant frogeye leaf spot in high inoculum areas.
• May 13, 2009
  • Kearneysville Maryblyt forecast and summary. Check here for symptom development predictions.
  • A report from a home owner suggsts that fire blight blossom infection occurred on April 25-26 in Jefferson County (he was cutting out blossom strikes this past weekend). As you may recall, we did not track this potential infection because we did not experience a wetting event.
• May 11 - 12, 2009
  • Wet for 16 hours at 50 ° F with 0.14 inches of rain. Apple scab infection period #12. Probably a little on the cool side for cedar apple rust infection.
• May 9, 2009
  • Wet for 9 hours at 63 ° F with 0.06 inches of rain. Apple scab infection period #11. Cedar apple rust and quince rust infection period.
• May 6 - 7, 2009
  • Wet for 20 hours at 60 ° F with 0.14 inches of rain. Apple scab infection period #10. Heavy cedar apple rust and quince rust infection period. Photo
• May 5 - 6, 2009
  • Wet for 16 hours at 54° F with 0.27 inches of rain. Apple scab infection period #9. Heavy cedar apple rust and quince rust infection period.
• May 3 - 5, 2009
  • Wet for 46 hours at 53° F with 1.57 inches of rain. Apple scab infection period #8. Heavy cedar apple rust and quince rust infection period.
  • Secondary mildew observed at Winchester Fruit Lab.
• May 4, 2009
  • Continuing wetting period that began at 7:00 AM on May 3.
• May 3, 2009
  • Wet for 24 hours at 55° F with 0.63 inches of rain. Favorable for apple scab, rust, black rot, frogeye leaf spot, and peach scab (to name just the most important ones...).
• May 2, 2009
  • Wet for 7 hours at 58° F with 0.11 inches of rain. Favorable for rust infection.
• May 1, 2009
  • Wet for 9 hours at 64° F with 0.15 inches of rain. Apple scab infection period #7. Rust infection period. Fire blight infection (#2).
• April 30, 2009
  • Wet on and off yesterday (April 29) with 7 hours of continuous wetting at 52° F with 0.10 inches of rain. This is NOT an apple scab infection period according to the revised Mills table, however, extended wetting and/or extended conditions of high relative humidity at other locations could easily satisfy the conditions for a light infection (12 hours at 52° F).
  • Apple scab lesions observed at Winchester Fruit Lab.
• April 29, 2009
  • The weather forecast and stage of plant development suggests we may experience conditions favorable for quince rust and cedar apple rust infection over the next several days.
• April 28, 2009
  • Apple scab ascospore maturity model indicates 90% ascospore maturity. I would expect a siginficant ascospore release with the next wetting event, which is forecasted for tomorrow and Thursday.
• April 21, 2009
  • April 19-21. Wet for 34 hours at 48° F with 1.43 inches of rain. With rain beginning at 11:00 PM, April 19, and continuing with intermittent and ocassionally steady rainfall, our sixth scab infection period is a "heavy" infection according to the Mills Table. These conditions are marginally favorable for cedar apple rust infection; there was no predominant wind direction during this infection period.
• April 20, 2009
  • Apple scab infection period in progress. Estimated ascospore maturity is 60% (peak).
• April 17, 2009
  • Open bloom reported on April 13 on Idared at Winchester AREC.
  • Apple scab infection forecast: Light infection associated with rain beginning Sunday evening and continuing into Monday, with temperatures in the high 40's. Significant rainfall (0.85 inches) is predicted.
• April 16, 2009
  • April 13-16. Wet for 48 hours at 44° F with 0.49 inches of rain. With rain beginning at 7:00 PM, April 13, and continuing with intermittent and ocassionally steady rainfall, our fifth scab infection period is the most severe to this date ("heavy" infection on the Mills Table). These conditions are marginally favorable for cedar apple rust infection, although we were close to the marginal low temperature limit for basidiospore formation for most of the wetting duration. Cedar apple rust infection often is facilitated by a favorable wind direction from cedar rust inoculum trees. Our predominant wind direction during this infection period was north/northeast.
• April 14, 2009
  • Apple scab infection period in progress.
• April 13, 2009
  • Apple scab infection forecast: Light infection associated with rain beginning Monday night and continuing wet through Wednesday, with temperatures in the low 40's.
• April 11, 2009
  • Wet for 10 hours at 48° F with 0.74 inches of rain. This was not an infection period.
• April 7, 2009
  • eTwilight meeting - online handouts:
    • Insect Management
    • Disease Management
• April 6, 2009
  • Windy and occasionally wet, but not long enough for a scab infection period. Current bud stage on early varieties is early tight cluster to tight cluster.
• April 3, 2009
  • April 3. Wet for 13 hours with 0.90 inches of rain. With rain beginning at 1:00 AM, the scab infection period begins at daybreak, for 9 hours of wetting at 59.8° F. This is a "light" apple scab infection period - our fourth. These conditions are favorable also for cedar apple rust infection, with an average temperature of 59.8° F over a 13-hour period. Cedar apple rust infection often is facilitated by a favorable wind direction from cedar rust inoculum trees. Our predominant wind direction during this infection period was southeast/east-southeast.
• April 2, 2009
  • April 1-2. A split wetting period and extended dew combine for 14 hours of wetting at 49° F, with 0.09 inches of rain. This is our third apple scab infection period. This one may be marginal for some locations or of greater severity at other locations.
  • It's time to get the upper hand against apple powdery mildew. Spores are available from overwintering infections. Mildew-susceptible varieties should be protected. A "mildew day" has temperature during the day over 60° F and no rain.
• March 30, 2009
  • March 27-29. Wet for 37 hours with 0.95 inches of rain. Wetting period for apple scab calculated as wet for 29 hours at 51° F (shortened due to initiation of wetting during night time and two intervening dry periods between rain events). This is our second apple scab infection period.
• March 27, 2009
  • March 25-27. Wet for 38 hours with 0.34 inches of rain. Wetting period for apple scab calculated as wet for 28 hours at 43° F (shortened due to initiation of wetting during night time). Ascospores caught in spore traps at Winchester AREC. This is our first apple scab infection period.
• March 23, 2009
  • I am seeing a lot of green tip stage on Red Delicious, and later stages on some other varieties (Granny Smith, Braeburn) at KTFREC. This is about a week earlier than in 2008. Copper applied at this time will help manage fire blight and will control early scab infections. The weather forecast would seem to indicate the potential for favorable scab infection weather on March 27-28.
• Average daily temperatures and records
• Average last freeze date map

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