Current Insect and Disease Conditions at KTFREC
   

Fruit Tree Books

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.  

Click for Kearneysville, West Virginia Forecast ladybug1.gif (1229 bytes)Weekly pheromone trap data and degree-day accumulations (updated every M-W-F) from WVU/Kearneysville.
(2014 trap data and degree-days)  
     
Link to KTFREC weather station NOAA Climate Forecast  
  • August 20 - 21, 2014
    • Rain began at 3 PM on 8/20 and leaves remained wet through the morning of 8/21, with total rainfall accumulation of 0.59 inches during this 15-hour long wet period. Average temperature during the wet period was 67 F (infection period #29).
  • August 13, 2014
    • Rain began at 12 AM on 8/13 and leaves remained wet through the morning of 8/13, with total rainfall accumulation of 0.03 inches during this 8-hour long wet period. Average temperature during the wet period was 67 F (infection period #28).
  • August 11 - 12, 2014
    • Rain began at 5 PM on 8/11 and leaves remained wet through 11 AM the morning of 8/12, with total rainfall accumulation of 0.96 inches during this 17-hour long wet period. Average temperature during the wet period was 72 F (infection period #27).
    • Watch for fungicide removal and favorable conditions for bitter rot development.
  • August 6 - 7, 2014
    • Rain began at 10 AM on 8/6 and leaves remained wet through the morning of 8/7, with total rainfall accumulation of 0.15 inches during this 17-hour long wet period. Average temperature during the wet period was 70 F (infection period #26).
  • August 3 - 4, 2014
    • Rain began at 7 PM on 8/3 and leaves remained wet through the morning of 8/4, with total rainfall accumulation of 0.41 inches during this 15-hour long wet period. Average temperature during the wet period was 64 F (infection period #25).
  • July 30, 2014
    • Accumulated wetting hours (AWH) = 381.
  • July 27 - 28, 2014
    • Rain began at 11 PM on 7/27 and leaves remained wet through the morning of 7/28, with total rainfall accumulation of 0.20 inches during this 9-hour long wet period. Average temperature during the wet period was 67 F (infection period #24).
  • July 26 - 27, 2014
    • Rain began at 10 PM on 7/26 and leaves remained wet intermittantly through the morning of 7/27, with total rainfall accumulation of 0.32 inches during this 11-hour long wet period. Average temperature during the wet period was 68.5 F (infection period #23).
  • July 15, 2014
    • Rain began at 3 PM on 7/14 and leaves remained wet intermittantly through the morning of 7/15, with total rainfall accumulation of 0.81 inches during this 14-hour long wet period. Average temperature during the wet period was 72 F (infection period #22). Note that wet periods with temperatures in the 70'sare favorable for bitter rot infections. Growers are reminded to re-apply protective-type fungicides after 2 inches of accumulated rainfall within the normal 14-to-21-day reapplication interval.
    • Sooty blotch signs and symptoms are being reported from non-sprayed apple trees at the Winchester AREC.
  • July 14, 2014
    • Rain began at 6 PM on 7/13 and leaves remained wet continuously through the morning of 7/14, with total rainfall accumulation of 1.13 inches during this 14-hour long wet period. Average temperature during the wet period was 70 F (infection period #21). Note that wet periods with temperatures in the 70'sare favorable for bitter rot infections.
    • Accumulated wetting hours (AWH) = 300.
  • July 9, 2014
    • Rain began at 6 PM on 7/8 and leaves remained wet continuously through the morning of 7/9, with total rainfall accumulation of 0.28 inches during this 10-hour long wet period. Average temperature during the wet period was 70 F (infection period #20). Note that wet periods with temperatures in the 70'sare favorable for bitter rot infections.
  • July 7, 2014
    • Accumulated wetting hours (AWH) = 249. This is, for all practical purposes, the early threshold of 250 accumulated wetting hours for treatments specifically directed towards management of the sooty blotch and flyspeck organisms.The wetting hour threshold indicates when we have confidence that the SB&FS organisms are present but not yet visible on unprotected fruit. Remember to scout your problem orchard areas regularly for first SB&FS appearance.
  • June 30, 2014
    • Accumulated wetting hours (AWH) = 228. Approaching the early threshold of 250 accumulated wetting hours for treatments specifically directed towards management of the sooty blotch and flyspeck organisms.
  • June 25, 2014
    • Rain began at 8 PM on 6/25 and leaves remained wet continuously through the morning of 6/26 until about 2 AM, with total rainfall accumulation of 0.16 inches during this 7-hour long wet period. Average temperature during the wet period was 71 F (infection period #19). Note that wet periods with temperatures in the 70'sare favorable for bitter rot infections.
  • June 21, 2014
    • Rain began at 6 AM 6/21 and leaves remained wet through noon that day, with total rainfall accumulation of 0.12 inches during this 7-hour long wet period. Average temperature during the wet period was 65 F (infection period #18).
  • June 19 - 20, 2014
    • Rain began at 7 PM on 6/19 and leaves remained wet continuously through the morning of 6/20 until about 8 AM, with total rainfall accumulation of 0.42 inches during this 14-hour long wet period. Average temperature during the wet period was 66 F (infection period #17).
  • June 11 - 12, 2014
    • Rain began at 7 PM on 6/11 and leaves remained wet continuously through the morning of 6/12 until about 8 AM, with total rainfall accumulation of 1.37 inches during this 14-hour long wet period. Average temperature during the wet period was 68 F (infection period #16).
    • Be aware of fungicide "wash off" events and re-apply protective materials when needed. We use 2 inches of rain as a guideline to assess re-application intervals for disease management on apples.
    • Accumulated wetting hours (AWH) = 145.
  • June 10 - 11, 2014
    • Rain began at 10 PM on 6/10 and leaves remained wet continuously through the morning of 6/11 until about 9 AM, with total rainfall accumulation of 0.33 inches during this 12-hour long wet period. Average temperature during the wet period was 66.5 F (infection period #15).
  • June 9, 2014
    • Rain began at 9 PM on 6/8 and leaves remained wet continuously through the morning of 6/9 until about 10 AM, with total rainfall accumulation of 0.11 inches during this 14-hour long wet period. Average temperature during the wet period was 67 F (infection period #14)
    • Accumulated wetting hours (AWH) as of 10 AM this morning = 119.
  • June 5, 2014
    • Rain began at 10 PM on 6/4 and leaves remained wet continuously through the morning of 6/5 until about 9 AM, with total rainfall accumulation of 0.54 inches during this 12-hour long wet period. Average temperature during the wet period was 63 F (infection period #13).
  • June 4, 2014
    • Fire blight is severe in some locations and will look a lot worse in about 10 days. We are beginning to easily visualize the effects of 8 infection events in a row during the period from May 8 to 15. With an additional infection event on May 22, that makes 9 infection events for the season. We are seeing quite a bit of fire blight on apple cultivars Paula Red, Golden Delicious, and Rome. Symptoms for these blossom infection events became visible over the period 5/15 to 6/1. Canker blight and shoot blight symptoms started showing up on 5/23 and 5/27, respectively, according to the Maryblyt model, although I observed shoot blight a few days earlier than 5/27.
    • Cedar apple rust bonanza! A classic case of cedar apple rust that has turned trees entirely yellowish-gold can be seen at the Deerfield Village development along Rt. 480 between Kearneysville and Shepherdstown. Although we see the disease there almost every year, it is exceptional in its appearance this year. The Golden Delicious trees are yellow and the Red Delicious trees are green (because they are resistant to the pathogen). This is a "wow" thing for plant pathologists.
    • AWH = 79 on June 4.
    • The current weather pattern is excellent for powdery mildew infections on new growth.
  • May 29 - 30, 2014
    • Rain began at 4 AM on 5/29 and leaves remained wet almost continuously through the morning of 5/30 until about 9 AM, with total rainfall accumulation of 0.18 inches during this 23-hour long wet period. Average temperature during the wet period was 57 F (infection period #12).
    • Total rainfall accumulation for May 2014 = 4.01 inches (note that my May 2 long range forecast was for 30% below normal precipitation - we actually got about 10% above normal).
    • AWH = 63 on May 30.
  • May 27 - 28, 2014
    • Rain began at 6 PM on 5/27 and leaves remained wet continuously through the morning of 5/28 until about 5 AM, with total rainfall accumulation of 0.34 inches during this 12-hour long wet period. Average temperature during the wet period was 68 F (infection period #11).
  • May 22, 2014
    • Fire blight risk today is INFECTION with this morning's rainfall (0.28 inches at KTFREC), open blossoms, and favorable temperatures.
    • Begin accumulating wetting hours for sooty blotch and flyspeck forecasting (based on petal fall date for Golden Delicious = May 12).
  • May 20, 2014
    • Fire blight risk is INFECTION for trees with open blossoms and if wetting occurs on each day from May 21 through May 24 (based on the 5-day forecast issued on May 20).
  • May 16, 2014
    • May 15 - 16, 2014. Rain began at 5 PM on 5/15 and leaves remained wet continuously through the morning of 5/16 until about 8 AM, with total rainfall accumulation of 2.85 inches during this 16-hour long wet period. Average temperature during the wet period was 60 F (infection period #10).
  • May 15, 2014
    • Fire blight risk is INFECTION today if moisture occurs (30% chance). After today, the next day that is favorable for infection is next Thursday 5/22. This forecast could change if actual temperatures are warmer than those published today's forecast. There is still a significant amount of bloom on Rome apple trees at KTFREC.
    • Growers should consider applying Apogee to limit succulent shoot growth and thereby reduce the risk of significant shoot blight occurring following this intense period of optimum conditions for fire blight blossom infection.
    • Cedar apple rust on foliage is showing up this week on non-sprayed trees in our research plots. We're finding the fungus on some of the older leaves, most likely from the 4/28 - 5/1 infection period.
  • May 14, 2014
  • May 13, 2014
    • May 12 - 13, 2014. Rain began at 7 PM on 5/12 and leaves remained wet continuously through the morning at 9 AM on 5/12, with total rainfall accumulation of 0.13 inches during this 11-hour long wet period. Average temperature during the wet period was 65 F (infection period #8).
  • May 11, 2014
    • May 10 - 11, 2014. Rain began at 1 PM on 5/10 and leaves remained wet continuously through the morning at 6 AM on 5/11, with total rainfall accumulation of 0.55 inches during this 16-hour long wet period. Average temperature during the wet period was 65 F (infection period #7).
  • May 9, 2014
    • The 10-day forecast shows HIGH or INFECTION fire blight risk through May 16. The situation changed on Thursday May 8 as heat poured into our area and open blossoms (B), EIP (H), and average daily temperature (T) are all favorable (Risk Level = HIGH, or INFECTION if you had 0.10 inch of rain or more on 5/7); therefore, from May 8 to 16, any moisture (W) will result in fire blight blossom infection (I). Remember, in years when frost occurs at the tight cluster stage of development, there is often a prolonged period of secondary bloom that often leads to what we call "a bad fire blight year." We are potentially looking at rapid symptom development from the May 8 infection period with first blossom blight symptoms visible on 5/16. Be aware that EIP and the threat of infection can build up rapidly if warmer weather than that forecasted occurs.
  • May 7, 2014
    • A locally heavy downpour at KTFREC left 0.47 inches of precipitation beginning at 11 AM and with leaves drying off by 2 PM resulting in about 4 hours of wetting at 51 F. Not an infection period for our fungus diseases, BUT... this rain event provided the conditions necessary for Maryblyt to forecast an INFECTION risk event on 5/8.
  • May 6, 2014
    • May 5 - 6, 2014, Rain began at 7 PM on 5/5 and leaves remained wet continuously through the morning at 8 AM on 5/6, with total rainfall accumulation of 0.13 inches during this 14-hour long wet period. Average temperature during the wet period was 49 F (infection period #6). Secondary infection was likely if primary infections are established.
    • There are visible apple scab lesions on nonsprayed Golden Delicious flower cluster leaves in our research plots. These look like they've been visible for a few days, as sporulation is easily seen. It is possible that some of these were sporulating during our 4/28-5/1 long wet period. It is time to scout for these and determine whether or not you have secondary inoculum present in your orchards. (Picture here).
  • May 5, 2014
  • May 2, 2014
  • May 1, 2014
    • Rain began at 4 PM on 4/28 and leaves remained wet almost continuously through Thursday morning at 9 AM on 5/1, with total rainfall accumulation of 1.62 inches during this 63-hour long wet period. Average temperature during the wet period was 49.6 F, with temperatures in the mid-50's at the beginning and end of the wet period. These conditions are excellent for apple scab and potentially favorable for quince rust and cedar rust infections, given the window of favorable temperatures and appropriate developmental stage of apple trees at this time. Fungicides that contain a sterol-inhibitor are very effective for after-infection control of rust fungi on apple (infection period #5).
    • This was NOT a fire blight infection period (see yesterday's Maryblyt forecast below). Day time temperatures will start to heat up next Thursday - watch the forecast and check here for updates.
    • The 10-day forecast looks favorable for apple powdery mildew.
    • Anyone with peaches past the shuck split stage of development would be at risk for peach scab infection during this wet period.
  • April 30, 2014
  • April 25, 2014
    • Rain beginning at 3:00 PM on April 25 with leaf wetness continuing intermittantly through 1:00 AM on April 26. We had 8 hours of wetting at an average temperature of 55.0 F with 0.97 inches of precipitation (infection period #4). This infection period was favorable for apple scab infection.
  • April 24, 2014
  • April 23, 2014
    • Spotty and erratic rain events yesterday can be puzzling when it comes to calculating apple scab infection periods. In the early afternoon we had 4 hours of wetting at an average temperature of 66 F, followed by several hours of dry weather. Later in the evening, at about 8 PM, we had some heavier rain that resulted in 3 hours of wetting at an average temperature of 56 F. Total rainfall at KTFREC was 0.22 inches. We will call this infection period #3, according to the model parameters described by Stensvand (1997).
    • There is no change in the fire blight forecast from what I posted yesterday.
  • April 22, 2014
  • April 15, 2014
    • Rain beginning at 5:00 AM on April 15 with leaf wetness continuing through 7:00 PM on that day. We had 15 hours of wetting at an average temperature of 53.8 F with 0.67 inches of precipitation (infection period #2). This infection period was favorable for apple scab infection.
    • About 7 or 8 hours of the wet period was in the 60's, thus providing favorable conditions for cedar apple rust and quince rust infections. DMI fungicides are the best bet for after-infection activity against rust infections.
    • Dry weather with temperatures above 53 F are favorable for apple powdery mildew infection, as mildew conidia are available to cause new infections at about the tight cluster stage of development.
  • April 8, 2014
    • Rain beginning at 7:00 AM on April 7 with leaf wetness continuing through 9:00 AM on April 8. 27 hours of wetting at an average temperature of 41.8 F with 0.43 inches of precipitation (infection period #1). Some green tip on early apple culitvars.
  • April 7, 2014
    • Apple scab infections are likely today, with about 18 hours of wetting at 43 F required for infection to occur, and about 11 hours of wetting at 50 F. We will be in that temperature range all day and it is likely that buds showing green tip will be wet through the night and into tomorrow morning. Copper applied recently should provide adequate protection. An option with after-infection activity would be copper + Vanguard.
  • April 1, 2014
    • Apples showing green tissue will need protection from the season's first ascospores prior to our next rain event. For after-infection applications consider using Vangard + copper, but no later than the 1/4-inch green stage on fresh market cultivars.
    • Insect update: Management of early season insect pests, Provided by Dr. Daniel Frank:
      Pre-bloom is the best time to control San Jose scale and rosy apple aphid in orchards. Target these insects with a silver-tip or ¼ - ½ inch green tip spray.  Products such as horticultural oil, chlorpyrifos (e.g. Lorsban, Nufos, Yuma), Supracide, Esteem, or Centaur (for San Jose scale only) can be used effectively during the silver-tip to green-tip period.  At ¼ - ½ inch green-tip, insecticides such as Beleaf and Endigo provide excellent control of rosy apple aphid, while horticultural oil, chlorpyrifos, and Supracide are recommended for San Jose scale.  As a reminder, chlorpyrifos can be applied once during the pre-bloom season (only as a foliar spray), or as a trunk application for control of dogwood borer pre- or post-bloom.  If dogwood borer is a concern you may want to consider alternating the use of chlorpyrifos for borer management every other year.  Also, be aware that horticultural oil and Captan are not compatible.  If managing early season pests with oil, alternative fungicides will need to be considered for apple scab management during this time. As a final reminder, spray coverage is critical for successful control of San Jose scale and rosy apple aphid.  Use as close to a dilute application as possible and apply sprays at slow travel speeds under optimum weather conditions (i.e. wind speeds less than 5 MPH). 
  • March 29 - 30, 2014
    • First apple scab ascospores caught in traps at the Winchester AREC.
  • March 31, 2014
    • Disease Management Reminders (while there’s still time!)
      Peach leaf curl
      should be controlled in the spring with a fungicide application before the buds swell, unless you already made a leaf curl application in the fall. If leaf curl was severe in your peach and nectarine blocks in 2013, and you made your fall fungicide application to control the disease for 2014, a spring fungicide application will be needed to ensure complete disease control. In orchards where careful monitoring is practiced and where leaf curl has not been present for two or more years, this spray can be omitted until the disease begins to recur. For best control of peach leaf curl, make a dilute application of fungicide under calm conditions, making sure to cover each bud thoroughly. Using one of the fixed coppers for the leaf curl spray may help suppress bacterial spot in blocks where this disease is a problem. See the Spray Bulletin for fungicides and rates of application.
    • Apple scab urea application: A spray of 5% solution of urea (46-0-0) in water may be applied as late as green tip to apple leaves on the ground if this was not done in the autumn (42 lb. urea in 100 gal. water, applied at 100 gallons/acre). The nitrogen will hasten leaf litter decomposition and will result in reduced ascospore production by 60 to 90%, thereby changing high-inoculum orchards into low-inoculum orchards. Moving leaves from under the trees to the row middles with a leaf blower and then shredding them with a flail mower is a good alternative to the urea spray for small acreages on level land (mud, rocks, and weeds can turn this into a futile exercise). If you had enough scab that you easily noticed it at the end of last year’s growing season, one of these inoculum reduction measures should be implemented. If the urea spray is used, remember to reduce other nitrogen applications accordingly. I estimate that about half of the urea nitrogen will land in the sodded row middles, and thus will not be available to the trees.
  • Spring will be here soon! Will you be ready?
  • Average daily temperatures and records
  • Average last freeze date map

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