Tag Archives: Winchester

Hard Freeze is Expected This Tuesday (March 29)

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Based on the weather forecast for Tuesday, March 29, temperatures will drop to 19 oF for a couple of hours (6:00 – 8:00 am) in the Frederick County and Rappahannock-Madison area, which could be devastating for the majority of apple cultivars and some early-bloom peach cultivars grown in these locations. Our apple cultivars in Winchester are currently in the tight-cluster stage, and some (e.g. Pink Lady and Zestar) are in the full pink-stage now. The majority of peach cultivars are in the pink stage now, with some early-blooming cultivars (e.g. John Boy) are already in bloom. Sweet cherries, on the other hand, are still in tight-cluster stage. Based on the critical temperature tables below, 90% of apple buds at tight-cluster can be killed if exposed to temperatures at 21oF and below for more than 30 min. Similarly, peach flowers at full bloom can be killed at the temperatures forecasted for Tuesday. Sweet cherry cultivars that are still in tight cluster will be likely OK, and only 10% can be damaged by this freeze event.

This is a typical advective freeze, accompanied by wind > 5 mph and dry air. Unfortunately, none of our frost mitigation measures, e.g., wind machines, overhead and under-tree sprinklers, can be of utility with this type of frost. Using any sprinklers, or spraying the tree with water using an air-blast or any other sprayer, will cause more damage than benefit. Heaters, on the other hand, can provide some protection if used for several hours, probably starting from midnight.

Tree fruit growers in the Nelson County may also face a brief, less damaging frost event, with the lowest temperature predicted to reach 24 oF before sunrise. Based on the current forecast, no frost/freeze is predicted for Roanoke and Carroll-Patrick counties.

Source:New Mexico State University
Source:New Mexico State University

Accede: a new chemical thinning material for apples and peaches

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Accede is a new thinning product from Valent BioSciences that you may need to consider for apple fruit thinning and peach blossom thinning. The active ingredient of this product is ACC (1-aminocyclopropanecarboxylic acid (ACC); a chemical that is produced naturally in plant as a precursor for ethylene (the ripening hormone). Unlike other ethylene-based products (e.g. ethephon), Accede doesn’t cause gummosis in peach and nectarine; and is not as aggressive when thinning apples. 

For apple fruit thinning: Accede can be used when the king fruit’s average fruit size ranges from 8-25 mm. However, this product is mainly intended for later thinning treatments (fruit size 15-18mm) when the primary thinning materials (e.g. 6-BA and NAA) are no longer effective. This product should be applied at a 23-46 fl oz/acre rate. A reduced rate should be considered if the temp on the day of application is >90 oF, and the best results are achieved under slow drying conditions (e.g., early morning, at night). 

For peaches and nectarines: Accede is the only labeled chemical thinning product. Unlike apple, Accede is mainly used as a bloom thinning treatment for peaches and nectarines. It should be applied between bloom and petal fall at 34-69 fl oz/acre rate. However, it was found that two applications (at 10% bloom and full-bloom), each at 34 fl oz/100 gal/acre, can achieve the best thinning results. The product works by causing early senescence to the flowers, thus preventing fertilization and fruit set of the unwanted crop. According to research conducted in MSU in 2021, two applications of Accede, reduced fruit set significantly and cut the time needed for hand-thinning in half, compared to untreated trees. 

Source: Dr. Anna Wallis, Apple Production Specialist at MSU

Precautions when using Accede for peaches and nectarines:

This product should not be applied to stressed, unhealthy trees as it may cause over-thinning. If frost occurs during bloom, you should wait until assessing the percentage of frost damage before applying Accede. The product should not be applied if rain is expected within 8h of application. Finally, this product should not be used for peaches and nectarines after petal fall.  

Here is a link for the product label for more information about Accede.

https://s3-us-west-1.amazonaws.com/agrian-cg-fs1-production/pdfs/AccedeTM_Plant_Growth_Regulator_Label.pdf

Winchester-Area Fruit Tour, July 16

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Final call for registration. If you’re interested in attending, please contact Mark Sutphin as soon as possible!

 

From Mark Sutphin:

We have a fantastic day tour of several Winchester area fruit operations scheduled for Thursday, July 16, 2015.  The tour will include orchards, vineyards, high tunnel fruit and vegetable production, a retail market, a packing operation, a cidery, a catered lunch, and an evening meal at Marker-Miller Farm Market.  We plan to arrange a coach for participants (coach to begin and end at National Fruit:  550 Fairmont Ave., Winchester, VA 22601).  There will also be other transportation and carpooling options planned as the need dictates.  If you are interested in this day tour, please complete the registration on the attached brochure and send in the registration fee of $30.00/each by July 8, 2015.

 

We continue to thank our Tree Fruit Program Sponsors for making this educational tour possible.  Please see the attached flyer listing our many faithful industry partners.

 

REGISTRATION FLYER: <Winchester VA Day Tour>

Mark Sutphin
Associate Extension Agent | Agriculture and Natural Resources, Horticulture | Unit Coordinator (Frederick)
 
Serving the counties of Frederick, Clarke, Page, Shenandoah, & Warren
 
Virginia Cooperative Extension – Frederick County Office | 107 North Kent Street | Winchester, VA 22601
Phone – 540.665.5699 | Fax – 540.722.8380 | Cell – 540.398.8148 | Email – mark.sutphin@vt.edu

9:30 am Stop 1: White House Foods (National Fruit Product Company)

David & Paige Gum

Glaize Packing House

12:00 pm Stop 2: Winchester Cider Works (catered lunch)

Diane Kearns & Stephen Schuurman

2:00 pm Stop 3: Glaize Raspberry High Tunnels

Philip Glaize, Jr. & Philip Glaize

 

3:30 pm Stop 4: Marker-Miller Orchards, Farm Market & Bakery

(includes: Benevino Vineyard) John Marker & Family

Joe Snapp & Family

Woodbine Farms

Harman Brumback & Family

 

6:00 pm Marker-Miller Orchards, Farm Market & Bakery (catered supper)

MaluSim models for 11 May 2015

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For both Winchester and Central Virginia, the Malusim model is predicting a mild to no carbohydrate stress over the next week. Although temperatures at the time of application, are less important then the carbohydrate running average (2+4 Running Average), expect chemical thinners applied Sunday (10 May) or Monday (11 May) to cause more thinning than applications made late last week or for the rest of this week. Expect a “typical” response from chemical thinners applied Tuesday (12 May) through the rest of this coming week.

Peck Winchester MaluSim 5_11_15Peck Central VA MaluSim 5_11_15

The National Weather Service is predicting sunny weather later this week, as well as daytime temperatures in the 70s. This should result in ideal conditions for plant growth, and thus less carbohydrate stress in the apple trees.

One of the weaknesses of weather-based models, is the need to use forecast data to make decisions about future events. When I ran the MaluSim models for both Winchester and Central Virginia last Thursday, the forecast was for hot, cloudy weather. Although it was in the mid-80s in most of Virginia over the weekend, there was also a lot more sunlight than predicted. Temperatures are generally a lot more reliable than cloud cover predictions, but both seemed to be less severe than originally forecasted.

Cloudy weather predicted for later in the week is causing wild swings in the MaluSim model output. My expectation is that actual carbohydrate levels will be more moderate and that running average values will remain in the 20 to -20 g CHO/day range.

Full model output:

Peck Winchester MaluSim 5_11_15.pptx

Peck Central VA MaluSim 5_11_15.pptx

MaluSim Model Data for 7 May 2015

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Due to warm days (>80F) and intermittent cloud cover, the MaluSim carbohydrate model is showing a strong carbohydrate deficit for both Winchester and Central Virginia over the next four to five days. Expect an aggressive to very aggressive response to chemical thinners applied today through early next week. Reduce rates, and/or do not include oil or other surfactants if overthinning is a concern.Peck Winchester MaluSim 5_7_15

Peck Central VA MaluSim 5_7_15

Pay close attention to the weather forecasts. If actual temperatures are closer to 90F and/or there are prolonged periods of cloud cover, then overthinning will likely occur.

The greatest amount of thinning occurs when fruitlets are on average between 8-12 mm in diameter. Thinning when fruitlets are slightly smaller or larger will result in less thinning, which may be desirable if there is a severe carbohydrate deficit.

Cooler temperatures forecasted for the middle to end of next week should result in less carbohydrate stress and reduced chances of overthinning. However, fruitlets that are greater than 15 mm in diameter are more difficult to thin with NAA or 6-BA.

During these warm days, expect the average fruitlet size to increase by at least 0.5 mm per day.

Full MaluSim model output:

Peck Winchester MaluSim 5_7_15.pptx

Peck Central VA MaluSim 5_7_15.pptx

2015 Winter Fruit Schools

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The 2015 Winter Fruit School dates, times, and locations have been set. These in-depth meetings focus on commercial tree-fruit production. The schedule will be similar to the 2014 schedule, with the Carroll-Patrick meeting occurring on Tuesday morning and the Central Virginia meeting occurring on Wednesday evening. The full list of locations is below, as well as the local contact for each meeting. NOTE: There is a new location for the Carroll-Patrick Fruit School meeting this year.

Presentations by will include the following topics: brown marmorated stink bug update, tall spindle systems, hard cider resources, neonicotinoid impacts on pollinators, spotted winged drosophila and spotted lanternfly updates, and summer disease management updates with a focus on Glomerella leaf spot. Additional programing is still being developed at each location and more details are forthcoming. Pesticide recertification credits are usually available, check with the local contact for more information.

Date Location Registration opens Local Contact Contact’s phone
number
Tuesday
February 10
<Program>		 Hungry Farmer Cafe
15297 Fancy Gap Highway (US 52)
Cana, VA 24317		 9:00AM Steve Pottorff 276-730-3113
Wednesday
February 11
<Program>		 Brambleton Center
3738 Brambleton Avenue SW 
Roanoke, VA 24018		 8:15AM Kate Lawrence 540-473-8260
Wednesday
February 11
<Program TBD>		 The Nelson Center
8445 Thomas Nelson Highway
Lovingston, VA 22949		 4:30PM Michael Lachance 434-263-4035
Thursday
February 12
<Program>		 Grave’s Mountain Lodge
Rte. 670
Syria, VA 22743		 8:15AM Kenner Love 540-675-3619
Friday
February 13
<Program &
Registration Form>		 Best Western-
Lee Jackson Banquet Hall
711 Millwood Ave. 
Winchester, VA 22601		 8:00AM Mark Sutphin
&
Marsha Wright		 540-665-5699

 

Apple Maturity Report for September 16

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We checked the maturity of apples growing at the Alson H. Smith, Jr. AREC on September 16.

With clear days, dry conditions, and cool nights we couldn’t ask for a better stretch of weather. Many growers are starting to pick their main cultivars, including Red Delicious and Golden Delicious. Data from the AREC show that both of these cultivars are still in an ideal window for long-term storage. Jonagolds and Empires are entering into the ideal harvest window. Idareds and Romes are probably a week or so away, and Yorks are probably two weeks away from their ideal harvest maturity.

Below are all of our harvest data for 2014.  Click on this sentence to learn more about the different maturity indices.

Maturity Report 2014, Virginia Tech        
Sample Collection Date Cultivar Location Number of Orchards Tested (10 Fruit Each) Background Color (1-4)* Red Color (%) Firmness (lbs) Soluble Solids (ºBrix) Starch-iodine Index       (1-8)** Fruit Diameter (inches) Fruit wt. (g) Ethylene (ppm)
8/18/14 Gala (Crimson) AHS JR AREC 1 – 80.4 23.2 11.2 1.1 2.66 144 0.0
8/25/14 Gala (Crimson) AHS JR AREC 1 – 93.2 20.0 13.3 3.4 2.79 162 0.4
8/25/14 Gala (Buckeye) AHS JR AREC 1 – 98.7 21.6 14.9 4.0 2.79 172 1.6
8/18/14 Golden Supreme AHS JR AREC 1 3.1 – 18.1 10.9 1.7 2.88 174 0.0
8/25/14 Golden Supreme AHS JR AREC 1 2.6 – 16.9 11.5 2.6 2.82 166 0.0
8/25/14 Golden Delicious Winchester 12 2.2 – 18.6 12.4 1.5 2.85 166 0.0
9/16/14 Golden Delicious Winchester 2 2.9 – 16.3 13.5 4.6 2.82 161 0.0
8/18/14 Honeycrisp AHS JR AREC 1 – 53 18.5 11.8 1.1 3.27 232 0.0
8/25/14 Honeycrisp AHS JR AREC 1 – 55 15.8 13.0 1.8 3.36 247 4.9
8/25/14 Red Delicious (Scarlet Spur) Winchester 1 – 91 19.2 10.9 1.3 2.90 179 0.0
8/25/14 Red Delicious (Red Chief) Winchester 2 – 80 19.3 10.6 1.2 2.92 182 0.0
8/25/14 Red Delicious (Nured) AHS JR AREC 1 – 87 18.0 9.8 1.1 2.83 166 0.0
8/25/14 Red Delicious (Redspur) Winchester 1 – 64 18.6 11.2 2.1 2.93 182 0.0
8/25/14 Red Delicious (Ace) AHS JR AREC 1 – 95 19.7 10.8 1.0 2.78 160 0.0
8/25/14 Red Delicious (Bisbee) AHS JR AREC 2 – 86 18.9 10.9 1.3 2.80 163 0.0
9/16/14 Red Delicious (Nured) AHS JR AREC 1 – 97 17.0 11.7 2.4 2.83 167 0.9
9/16/14 Red Delicious (Ace) AHS JR AREC 1 – 99 19.2 13.0 2.0 2.93 187 3.6
8/25/14 Empire AHS JR AREC 3 – 64 18.8 11.7 1.6 2.82 148 0.0
9/16/14 Empire AHS JR AREC 1 – 88 18.3 12.6 2.7 2.65 126 0.6
9/16/14 Rome (Law) AHS JR AREC 1 – 92 21.7 12.2 3.0 2.92 163 0.3
9/16/14 Rome (Taylor) AHS JR AREC 1 – 50 21.6 12.4 3.0 3.14 203 0.0
9/16/14 York AHS JR AREC 2 – 80 23.8 11.1 1.3 2.90 161 0.0
9/16/14 Jonagold AHS JR AREC 1 – 81 16.3 14.2 5.4 3.30 251 0.1
9/16/14 Idared AHS JR AREC 1  – 61 15.2 12.9 2.0 3.00 180 0.0
* 1 = green, 2 = light green, 3 = yellowish green, 4 = yellow.
** 1 = 100% starch, 5 = 60% starch, 8 = 0% starch.

 

Predicted 2014 Apple Harvest Dates

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Predicting harvest date depends upon many factors, including full bloom date, accumulated heat units (growing degree days) over the course of the growing season, physiological stressors (e.g., disease and insect damage or drought), day to night temperature differentials as harvest approaches, and the amount of precipitation. However, the number of days between full bloom and harvest has been shown to be the most reliable predictor of harvest date.

Click here to learn more about pre-harvest drop management.

More than two decades ago, researchers in Michigan determined that there there are an average of 143 days between full bloom and the first commercial pick of Red Delicious apples that are to be held in controlled atmosphere storage (i.e., firmness between 17-18 lbs; starch between 2.5-4 on the 8-pt scale Cornell Starch Chart). Additional seasonal adjustments above or below the average number of days until harvest are made based upon the average daily minimum temperatures for the 15 days after full bloom.

For the past several seasons I have tested the Michigan model using fruit from a block of Bisbee Red Delicious on MARK rootstock. Results to date have shown that this model is very good at predicting harvest maturity in Virginia.

Based on the Michigan model, here are the predictions for 2014:

In Winchester, Bisbee Red Delicious full bloom was April 27 and average minimum temperature for the 15 days after full bloom was 0.5°F more than 50°F. Using this data in the Michigan model, harvest is predicted to be 143 days after full bloom. This puts the predicted harvest date for the first CA pick of Red Delicious at September 16.

In Central Virginia (Tyro), full bloom for Red Delicious was estimated to be April 20 and the predicted harvest is September 9.

If you want to compare the model to your own situation, here are the previous years’ predicted harvest dates:

2011 Winchester: September 10
2012 Winchester: August 26
2012 Central VA (Batesville): August 25
2013 Winchester: September 18
2013 Central VA (Piney River): September 15

Since most growers have Red Delicious trees in their orchards, other cultivars (and strains of Red Delicious that ripen earlier than Bisbee) can be estimated based upon experience on their picking date relative to Red Delicious.

Another method for estimating harvest date uses the rule-of-thumb that says, “for each 2-3 days departure for the normal bloom date, there will be a one-day departure from the normal harvest date.” (Blanpied and Silsby, 1992).

You can find more information about harvest maturity indices in this post.

Starting in August, I will start conducting maturity evaluations of fruit from the Winchester AREC and surrounding orchards.

References

Blanpied, G. and K. Silsby. 1992. Predicting Harvest Date Window for Apples. Cornell Information Bulletin 221. <<pdf>>

Beaudry, R., P. Schwallier, and M. Lennington. 1993. Apple Maturity Prediction: An Extension Tool to Aid Fruit Storage Decisions. HortTechnology 3(2): 233-239.

Central Virginia Orchard & Tree Fruit Day Tour – July 15, 2014

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We have a fantastic day tour of several Central Virginia orchards scheduled for Tuesday, July 15, 2014.  The tour will include high density (tall spindle) apple orchards, vineyards, retail markets, a packing operation, a cidery, a box lunch, and an evening meal on top of Carter Mountain overlooking Charlottesville, Virginia.  We will likely be traveling by coach from the Shenandoah Valley and there will be other transportation and carpooling options planned as the need dictates.  If you are interested in this day tour, please complete the registration on the attached brochure and send in the registration fee of $15.00/each by July 1, 2014.

Feel free to contact me for additional information or any clarifications.

We continue to thank our Tree Fruit Program Sponsors for making this educational tour possible.  Please see the attached flyer listing our many faithful industry partners.

Download the registration form: Central VA Tour Brochure <pdf>

Mark Sutphin

Associate Extension Agent | Agriculture and Natural Resources, Horticulture | Unit Coordinator (Frederick)

Virginia Cooperative Extension – Frederick County Office | 107 North Kent Street | Winchester, VA 22601

Phone – 540.665.5699 | Fax – 540.722.8380 | Cell – 540.398.8148 | Email – mark.sutphin@vt.edu | http://offices.ext.vt.edu/frederick/ | http://vacoopext.blogspot.com/

https://www.facebook.com/pages/VCE-Northern-Shenandoah-Valley-Agriculture-and-Natural-Resources/183932085102951

 

9:30 am Stop 1: Silver Creek Orchards (The Flippin Family) 

John & Ruth Saunders

5529 Crabtree Falls Highway, Tyro, VA

11:30 am Stop 2: Saunders Brothers (box/sandwich lunch)

Bennett Saunders & Family

2717 Tye Brook Highway, Piney River, VA

1:30 pm Stop 3: Crown Orchard Packing House* 

Chiles Family

5861 Piedmont Apple Ln., Covesville, VA

3:00 pm Stop 4: Albemarle Ciderworks 

Charlotte Shelton & Chuck Shelton

2545 Rural Ridge Ln., North Garden, VA

5:00 pm Stop 5: Carter Mountain Orchard (catered supper)

Chiles Family

1435 Carters Mountain Trail, Charlottesville, VA

The itinerary above is the proposed schedule and subject to change. 

* This is a GAP certified packing house and will require all visitors to abide by the following policies: guest sign-in, long pants must be worn, and no jewelry

MaluSim Carbohydrate Model for May 27, 2014

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I ran a MaluSim model using data from the weather station located at the Alson H. Smith, Jr. AREC in Winchester. This will be the last model run for the year.

Slide3 No forecast data was used in this run. Based on the output, I would expect chemical thinners that were applied May 14-16 to have an average response, while thinners that were applied on and after May 17 to have minimal effect. The effectiveness of thinners is greatly influenced by fruit size, so if the model showed a carbohydrate status that was greater than 20 g per day, and fruitlets were greater than 15 mm at the time of application then chemical thinners may not have been particularly effective.

Growers should compare the results of their chemical thinning program with the modeled carbohydrate status to determine if the model accurately predicted the level of thinning you expected from your applications.

I would appreciate hearing from growers about how they used the model to make chemical thinning decisions. Both positive and negative feedback is appreciated.  You can use the comment feature in the blog site, or just send me an email.

Download the full report:

Winchester VA MaluSim 5_27_14