Napa County UCCE
University of California
Napa County UCCE

European Grapevine Moth

Latest information on European Grapevine Moth for Napa County: Biology, monitoring and management

Issue Articles Type Date Added
Quarantine Boundary Revision (603KB)

USDA and CDFA have announced a change to the EGVM quarantine boundary that removes the following areas from regulation: 

southern portion of Napa County

remaining regulated portion of Solano County

majority of Sonoma County

Full details and a map of the current quarantine area can be accessed through the newsletter link below. 

PDF 8/28/14
Pre-Harvest Meetings--Napa County (279KB)

The Napa County Agricultural Commissioner has scheduled pre-harvest meetings to discuss  the European grapevine moth program. 

Wednesday, August 6 at 3:00 pm, Tucker Farm Center

Thursday, August 7 at 2:00 pm, Rutherford Grange

Tuesday, August 12 at 9:00 am, UC Cooperative Extension meeting room

They have applied for 1.0 continuing education unit ("other" category). 

Content will be the same at all meetings, so you need to attend only one. 

RSVP's are not required.

PDF 7/8/14
Detection in Sonoma County, California (223KB)

On July 2, 2014, we received the following report from CDFA:

The Sonoma County Agricultural Commissioner, in cooperation with the United States Department of Agriculture (USDA) and the California Department of Food and Agriculture (CDFA), announces the detection of a single male European Grapevine Moth (EGVM, Lobesia botrana) in the western portion of Sonoma County, near Cazadero.   The moth was identified on Thursday, June 26th in a trap from a vineyard.  

In response to the detection, agricultural officials immediately deployed delimitation traps at the rate of 100 traps per square mile.  A visual survey for EGVM eggs and larvae has been conducted and the results are negative.  The grower has been contacted. 

A single detection does not trigger a quarantine; however, if additional EGVM are detected within 3 miles of the original detection, a quarantine will be declared around the finds.  This area of Sonoma County has had no previous EGVM detections.  The closest previous detections of EGVM were over 20 miles away.  Agricultural officials are investigating this isolated EGVM detection.

Information on identification and management of L. botrana can be found on the UC Cooperative Extension websites for Sonoma and Napa Counties. Growers are encouraged to remain vigilant in scouting efforts, and practice sanitation and management practices in accordance with established quarantine and management programs. 

PDF 7/3/14
Tarp/slack-fill requirements relaxed for grapes transported within Napa County (267KB)
A request to relax the tarping/slack-filling requirements for the transport of bulk wine grapes moving within Napa County has been granted by CDFA and USDA and is being implemented as a pilot program for the 2013 harvest. Haulers who wish to take advantage of this pilot program are required to complete the exhibit and file a copy with the Napa County Agricultural Commissioner’s Office. This exhibit specifies that:
Only haulers transporting grapes within Napa County can conduct normal filling of trailers, conveyances and containers; and
Grapes grown within the EGVM Quarantine area of Napa County that are being transported to other counties must continue to be tarped or slack filled; and
PDF 9/3/13
2nd generation treatment timing for Napa County (28KB)

There are 11,550 EGVM traps deployed in Napa County. 

34 moths were captured during the 1st flight. 

To date, 2 moths of the 2nd flight have been captured.  

For the warmer regions of Napa (i.e; north of Oak Knoll): 

If you will be treating with a LARVICIDE/OVICIDE product, then applications can be made starting the week of June 17. If you will be treating with a LARVICIDE only product, then applications can be made starting the week of June 24. 

For the cooler regions of Napa:

If you will be treating with a LARVICIDE/OVICIDE product, then applications can be made starting the week of June 24. If you will be treating with a LARVICIDE only product, then applications can be made starting the week of July 1. 

Products with short residuals may require multiple applications during the hatch period. If you are in an area that is being treated with mating disruption in 2013 and you have not yet deployed dispensers, try to deploy them as soon as possible since the 2nd flight is very short. Insecticides should also be used in areas that are being treated with MD. 


PDF 6/11/13
A reminder for Napa County growers regarding grape shipments (24KB)

If you plan to ship winegrapes out of California or out of the country, you must notify the Napa County Agricultural Commissioner’s Office.  Certain time sensitive regulatory requirements must be met prior to such shipments occurring, including removal of mating disruption, and trapping and inspection by Ag Commissioner staff.  If you don’t meet the required time frames for shipping, grapes will need to be fumigated or shipped as must.  If you plan to sell grapes through a broker going out of state, the grower is still required to contact the Ag Commissioner prior to shipping fruit.   

If you plan to ship out of California or the United States, please contact Agricultural Biologist Greg Music: or (707)253-4357.  Thanks for your cooperation.

PDF 8/17/12
Insecticide Treatments for 2nd generation and Harvest Guidelines (88KB)

As of July 4, 2012, we have accumulated 1594 DDF in Oakville, CA. This is the appropriate time to apply insecticides targeting larvae of the 2nd generation in the regions of Napa that are similar in climate to Oakville. Growers using organic products should make two applications, at 7-10 day intervals. 

As of July 4, 2012, we have accumulated 1341 DDF in Carneros, CA. We should reach 1400 DDF next week. Products with ovicide-larvicide activity can be applied after we reach 1400 DDF (projected next week), in Carneros and other cooler regions of Napa. Products with larvicide activity only should not be applied until we have reached 1550 DDF

The Napa County Agricultural Commissioner would like to remind you of the importance of sanitation during the harvest season to minimize the risk of transporting Lobesia. Follow the newsletter link below to read about best practices for this harvest season. 

PDF 7/5/12
Insecticide treatments targeting the 2nd generation (39KB)

As of June 20, 2012, we have accumulated 1410 DDF in Oakville and 1180 DDF in Carneros. For areas other than Oakville and Carneros, please refer to the Table of Degree-Day Accumulations for Selected Locations in California.  

What this means for areas of Napa with climate similar to Oakville: 

If you are using an insecticide with ovicide and larvicide activity (such as Intrepid and Altacor), treatments can begin the week of June 24. 

If you are using an insecticide with larvicide activity only (such as organic products and conventional products other than Intrepid and Altacor), we must accumulate at least 1550 DDF before treating. We project this will be during the 1st week of July. 

What this means for areas of Napa with climate similar to Carneros:

If you are using an insecticide with ovicide and larvicide activity (such as Intrepid and Altacor), treatments can begin once we have accumulated 1400 DDF. We project this threshold will be reached in approximately 2 weeks. 

If you are using an insecticide with larvicide activity only (such as organic products and conventional products other than Intrepid and Altacor), treatments can begin once we have reached 1550 DDF. 


PDF 6/21/12
Treatment timing for 2nd generation Lobesia botrana in California (55KB)

Products with ovicide and larvicide activity (Intrepid and Altacor) should be applied after we have reached 1400 DDF (from January 1).

Products with only larvicidal activity should be applied after we have accumulated 1550 DDF (from January 1). Growers using organic products should expect to make 2 applications during the 2nd generation, at a 7 day interval.

In the warmer areas of Napa County, we expect to reach 1400 DDF during the week of June 25. Cooler regions could be 7-10 days behind.

As of June 10, we have accumulated 1029 DDF and 1230 DDF for Carneros and Oakville, respectively. We will post weekly updates of DDF accumulations for Carneros and Oakville.

If you have weather data from Calistoga, Pope Valley, or any other regions in Napa that differ from Oakville and Carneros, and are willing to share, we can use that information to make more accurate predictions about treatment timing for those regions.

Calculations used to determine treatment timing for 2nd generation: Lower and upper development thresholds are 50ºF (10ºC) and 86ºF (30ºC), respectively. Start date for degree day accumulations: January 1, 2012.

Heat unit accumulations from the literature (for the 1st and 2nd generations): 306 DDF = egg hatch to pupation                                                           234 DDF = pupa development to adult                          &nb

PDF 6/11/12
Monitoring Update (7KB)

We found 2, 1st instar larvae on Monday, 14-May. 

Of the eggs that we found, 19% had already hatched, 19% were ready to hatch (black cap), and 41% were in the yellow stage. 

This is the time to be treating for the 1st generation of Lobesia in Napa.  

PDF 5/15/12
Monitoring and Treatment Report (7KB)

It is time to treat for 1st generation Lobesia larvae in Napa County. Treatments should be applied between now and May 26.

A Napa Napa County trap deployed between Apr 24 and May 8 caught a total of 33 moths, confirming that peak of the 1st flight occurred towards the end of April. 

On May 9, we detected 66 eggs; 47% of these eggs were in the yellow stage, roughly mid-way through their development. Of the remaining eggs, 33% were white, 12% orange, and 8% black cap. We also found one larva (1st instar). This confirms that treatments will be effective if applied during the next 2 weeks. 

Please submit your Pesticide Use Reports for mating disruption by today's deadline. This critical information is used in many ways, and is of special interest to members of the Technical Working Group, who deliberate and make recommendations about the Lobesia program in California. As a member of the TWG, I can assure you that we do use this information, so please take a moment to provide it. 


PDF 5/10/12
1st flight and treatment update (34KB)

It is time to treat for the 1st generation of Lobesia larvae.  Ideally treatments should be applied between cluster elongation and the beginning of bloom. Applications should be made before 5% bloom.

Starting May 7, in Napa Valley and a week later in cooler areas, treatments can be combined with fungicide sprays anytime during the next 3 weeks. Hillside vineyards that are behind Oakville vineyards can be treated at the later end of the 2-3 week period, depending upon cluster development.  Organic growers will need to make multiple applications, at 7 to 10 day intervals.

We are inferring that the peak of the 1st flight of Lobesia in Napa occurred during the week of April 23. This is based on recent trap catches, degree-day model calculations, and our experience with Lobesia over the last 2 years.  

Most eggs are laid during the peak flight period. We expect these eggs to hatch in 118 DDF. From April 25 to May 2, we accumulated 93.22 DDF in Oakville. Once most eggs start hatching, there will be a window of 2-3 weeks to control small larvae.

For those following degree-days, here are historical numbers for Napa (Oakville CIMIS) for the peak of the 1st flight:
          2010: April 19 (485 DDF)
          2011: April 19 (572 DDF)
          2012: week of April 23 (588 DDF). 

PDF 5/4/12
Treatment guidelines for 2012 (247KB)

UC Treatment Guidelines for the 1st generation of 2012 are now available on the UC Cooperative Extension, Napa County website.

Also, if you missed the Industry meetings in Napa County this week, my presentation is also available.

PDF 2/17/12
Now available--Technical Working Group Report (66KB)

The Technical Working Group for Lobesia botrana has released their report, from meetings held Dec 13-15, 2011 in Sacramento, CA.

The report provides recommendations for regulatory policy and management practices for Lobesia botrana in California. Staff of USDA and CDFA use these recommendations to develop regulatory policy.

PDF 1/31/12
EGVM Industry Meetings to be held in February (110KB)

The Ag Commissioner's office will be holding three meetings to address the EGVM program in Napa County for 2012. The format will be identical for each meeting, so you need plan to attend only one. BUT, YOU SHOULD PLAN TO ATTEND, or send a representative, to learn about the recommended treatment program for 2012.

Yountville Community Center on Tuesday, Feb 14, 10 am to noon.
Tucker Farm Center (Calistoga) on Wednesday, Feb 15, 10 am to noon
Rutherford Grange on Thursday, Feb 16, 2 pm to 4 pm

Pre-registration is not required, but any questions regarding the meeting should be directed to the Ag Commissioner's office: 707-253-4357.

PDF 1/12/12
CDFA crews working in Napa and American Canyon (34KB)

CDFA crews will be working in the RESIDENTIAL AREAS of Napa and American Canyon. They will not be working in any commercial vineyards. They will be removing mating disruption dispensers. They plan to start work on November 7, and hopefully finish by November 23. There will be seven 3-person teams removing the dispensers.

Questions? Please contact John Cooledge, in the Ag Commissioner's office:   (707) 253-4357 or

PDF 11/2/11
Third flight update (6KB)

We caught one male today (9-September) in a Napa County vineyard trap. This is a male of the 3rd flight that was forecasted to start at the end of August in Napa.  

Any moths trapped after 2350 degree-days Fahrenheit (DDF) are considered moths of the 3rd flight. As of August 28, we had accumulated 2367 DDF in Oakville (Oakville CIMIS station data).

Treatments for the 3rd generation were not recommended by the Technical Working Group, except in the case of obvious damage or populations. 

PDF 9/9/11
EGVM Situation Report (117KB)

USDA-APHIS, CDFA, and California Agricultural Commissioners released a Situation Report on Lobesia botrana on August 27, 2011.

2011 catches in Napa County detection traps, by month:
April: 31 males
May: 60 males
June: 0 males
July: 15 males
Aug: 1 male

PDF 9/9/11
Movement of fruit under compliance agreements (51KB)

The Napa County Agricultural Commissioner and Staff have issued a progress report on EGVM activities in Napa. 

The report contains critical information on Compliance Agreements for the movement of fruit both within California and out-of-state. You must have an active compliance agreement to move or receive fruit grown in a quarantined area. Compliance agreements from 2010 are still in effect, unless you received an updated exhibit from the Agricultural Commissioner's office.

There are unique requirements for fruit moving out-of-state from the quarantined area. These are detailed in the newsletter file.

If you have any question on Compliance Agreements or fruit movement, please contact the staff of the Agricultural Commissioner: 253-4357

PDF 8/22/11
Situation Report for Lobesia botrana in California (119KB)

USDA-APHIS, CDFA, and California Agricultural Commissioners have released a "Situation Report for Lobesia botrana in California" as of July 16, 2011.

The report contains the most current detection trapping results, by California county, as well as the number of detection traps deployed per California county.

It also reports the most current information on fruit removal and other treatments in residential areas, and general information on quarantined areas.

Link to the newsletter below to access the full text of the report.

PDF 7/27/11
Lobesia life stage update for week ending July 22, 2011 (7KB)

No male moths caught in our UC traps this week. Males were caught in the the County-wide detection traps serviced by staff of the Napa County Ag Commissioner this week. Thus, the second flight continues in Napa.

Although we have not detected any eggs or larvae of the 2nd generation, we continue to project that peak flight and peak egg laying occured last week in Napa County. We are basing this on calculations using development models and field verification of populations during the 1st generation in Napa.  

Growers using conventional materials should have already made spray applications in Napa County, and growers using organic materials should have made their second and final treatments for this generation this week.

PDF 7/22/11
CDFA crews will be active in Napa this week (8KB)

California Department of Food and Agriculture (CDFA) crews will be working in the city of Napa this week. They are doing some ground verification planning for additional mating disruption activities that will occur in the next few weeks.
CDFA crews will also be working in the Carneros and Foster Road areas this week (July 12-15). They will be doing a 2nd round of fruit removal on non-commercial (mainly backyard) vines, only when owners have chosen not to treat with insecticides or harvest fruit.

Should you have any question about these activities, please contact the office of the Agricultural Commissioner of Napa County: (707) 253-4357.

If you have specific questions following an encounter with a member of a CDFA crew, please make note of the CDFA crew member's name. All crew members should be wearing their name badges. Having the name of the person you spoke with will  greatly increase the chances that staff of the Ag Commissioner can track down the information that you seek.

PDF 7/12/11
Male flight and egg update for week ending July 8, 2011 (7KB)

The 2nd flight continues as we caught one male this week in Napa County.

We still have not found any eggs, but populations are lower than they have ever been in Napa.

We continue to project that peak flight will occur next week (July 11-15).

If you have not already applied insecticides with ovicide/larvicide activity, they should be applied next week. Applications of insecticides with strictly larvicide activity should also be applied next week. Depending upon product residual, multiple applications of larvicidal materials may be required to cover the 2nd generation.

PDF 7/8/11
Male flight and life stage update for Napa for week ending July 1, 2011 (7KB)

We caught 2 males of the 2nd flight this week. We have not found any eggs yet, although populations are much smaller so we may not find any until peak egg laying (peak flight).

Based on our most recent calculations, we continue to predict that peak flight in Napa will occur from July 11-July 15.

Appropriate timing for insecticides with ovicide/larvicide activity is July 7-15.

Appropriate timing for insecticides with strictly larvicidal activity (organic and conventional) is the week of July 11. Depending upon the residual of the product, a 2nd application may be needed for this generation to cover the period of egg hatch and early larval development.

PDF 7/1/11
Update on trap catches for week ending June 24, 2011 (7KB)

We caught our first males of the 2nd flight today in Napa Valley. We caught 2 males in one trap.

We are predicting peak of the 2nd flight to occur during the week of July 11-15.

Conventional insecticides with ovicidal and larvicidal activity (Intrepid and Altacor) will be most effective when applied just prior to peak flight.

Organic insecticide applications targeting the 2nd generation should begin at peak flight, when eggs should begin hatching.

PDF 6/24/11
Life stage update for Napa--week ending Jun 17, 2011 (7KB)

80% of our sampled population is now in the pupal stage. The remaining 20% of larvae are older instars that we expect to pupate soon.

We have not yet caught moths of the 2nd flight. Catching the 1st moth of the 2nd flight will allow us to more accurately predict the spray schedule for the 2nd generation.

In 2010, there were ~21 calendar days and 359 DDF between the first moth catch and the peak of the 2nd flight. The first moth was caught on June 10, 2010 and the peak was the week of July 2, 2010.

Conventional insecticides with ovicidal and larvicidal activity (Intrepid and Altacor) will be most effective when applied just before peak flight. Organic insecticide applications targeting the 2nd generation should begin at peak flight.

PDF 6/17/11
Napa Trap and Larva Report for week ending June 3, 2011 (274KB)

No males in our traps again this week. The first flight of 2011 has ended. The 2nd flight has not yet started.

Cool weather has slowed larval development. Most larvae are 3rd instar or larger: 44% of sampled larvae were estimated to be 3rd instar, 18% estimated as 4th instar, and 36% estimated as 5th instar stage. We have not observed pupation yet.

This is still an excellent time to sample for larval damage. Link to the newsletter for four additional photographs of typical damage during bloom.

PDF 6/3/11
Lobesia larva report for Napa for week ending May 27, 2011 (151KB)

No male moths caught in traps again this week. The first flight appears to be over.

Larvae are developing. The majority are 3rd instars. They will grow through  2 more instar stages before they pupate. 

Bloom is an excellent time to SCOUT for larvae and damage. Link to the newsletter below for photographs of typical Lobesia feeding damage this time of year. Flower parts are webbed together, and larvae live and feed inside these nests.

PDF 5/27/11
Trap and life stage report for Napa County (7KB)

No males in UC traps in Napa County this week. Peak flight is over, and we expect the 1st flight to end within the next couple of weeks. 

There are early instar larvae in the field right now. 

It is important to have an insecticide residue on the flower clusters in Napa County. This requires repeated applications of organic products, and an application of a conventional product within the residual period suggested by the manufacturer.

PDF 5/12/11
Male flight and egg update from Napa County (7KB)

We are still catching males, but fewer than last week.

Eggs are hatching. We continue to find developing eggs as well as black cap eggs that are ready to hatch. Eggs will continue hatching into next week.

This is the time for insecticide applications in Napa County. Insecticide residues should be present for the period of egg hatch and early larval development.

Organic insecticides should be applied at regular intervals and conventional insecticides may be applied only once, if the residue is sufficient to cover this period.

PDF 5/5/11
Traps and Egg monitoring for week ending Apr 29, 2011 (13KB)

We caught 11 males in our traps this week. That is consistent with the peak flight period that we experienced last week, and the beginning of this week. Peak flight is the peak period for egg laying.  

We detected 4 new eggs this week (3 white, 1 yellow) that were deposited during the peak flight period. Eggs deposited during the peak period are projected to hatch by the end of next week (May 5, 6).

Eggs that we have been following since Apr 14, were at black cap stage or hatching by Thurs, Apr 28. This was approximately 65 DDC (116 DDF) between detection and hatch. This is consistent with figures from the literature: eggs hatch in approximately 66 DDC (118 DDF).

The first week of May is the optimal timing for insecticide treatments. Insecticides should not be applied unless the vines have at least 6 inches of shoot growth.

PDF 4/29/11
Male flight and Egg update for week ending Apr 22, 2011 (14KB)

We caught 13 males this week. We suspect this is peak flight. Peak flight is also the peak time for egg-laying. We monitored 8 eggs this week: 7 eggs are in the yellow stage, 1 is in the white stage.

We expect most eggs will hatch the first week of May, 2011.

The first week of May is the OPTIMAL timing for insecticide treatments. Vineyard blocks that are behind in development should not be treated until they have at least 6 inches of shoot growth. 

Conventional products with longer residuals products may be applied between Apr 27 and May 13. Applications of Organic products should begin at egg hatch (first week of May), and continue through egg hatch and early larval development.  

PDF 4/22/11
Trap catches for week ending Apr 15, 2011 (7KB)

No males in the UC-monitored pheromone traps, or the alimentary traps.

Napa Ag Comm staff found 5 males this week, in 3 of their traps.

Males are flying, and females are beginning to lay eggs on exposed flower clusters.

PDF 4/15/11
Egg report for week ending April 15, 2011 (7KB)

We found our first eggs this week.

In a block with 3-4 inches of shoot growth, we found one WHITE egg (recently laid).

In a block with 5-6 inches of shoot growth we found one WHITE and two YELLOW eggs.

This is consistent with 2010, when we recorded our first eggs at 3-4 inches of shoot growth.

Insecticide treatments should be applied at egg hatch.

(except vineyards in the Central Valley where 2 insecticide applications will be made.)

PDF 4/15/11
Trap catches for week ending 8-Apr-2011 (10KB)

No males in our pheromone-baited traps this week, although mating disruption dispensers have been deployed in the vineyards we are monitoring.

One male was caught in a trap baited with apple juice + pheromone, during the week of Mar 25 to Apr 1.

No males have been caught in the Napa County Ag Comm traps (~2700 traps, deployed since 14-Feb).

Although we are ahead of 2010 for degree day accumulations, we are behind on vine growth:

March 31, 2010: we saw our first eggs on CH in Oakville;
vines had 3-4 inches of growth; 197.66 DDC accumulated for EGVM

April 9, 2010: egg identification field day, CH in Oakville;
vines had 6-8 inches growth; 221.61 DDC accumulated for EGVM

The same plot on April 7, 2011: 1-2 inches of growth, no flower clusters;
221.61 DDC accumulated for EGVM

We will be out monitoring for eggs as soon as we have sufficient growth.

PDF 4/8/11
Degree-day update for week ending April 2, 2011 (90KB)

An updated table of degree-day accumulations for selected sites in California, corresponding to the week ending April 2, 2011. 

We will be posting weekly updates throughout the first and second flights and generations.

These weekly postings complement information published at

PDF 4/6/11
Using degree-day accumulations to time insecticide treatments (276KB)

We have written a brief explanation of the use of the degree-day models for timing of 1st generation insecticide treatments for Lobesia botrana.

In addition to this report, you can expect to receive weekly reports of degree-day accumulations, for various weather stations in California.

We will also report results our field surveys for life stages (eggs, larvae, pupae) that will be used to validate the degree-day models.

PDF 3/29/11
Napa County EGVM mapping application (11KB)

The mapping application for Napa County is back in service.

The map can be used to locate grids with positive moth finds during the 2010 season. This should help to determine treatment areas for 2011.

There have not yet been any moths found in Napa county traps in 2011, but as they are found, the map will be updated to reflect positive grids.

Directions for use and a link to the map can be found on the Napa County Agricultural Commissioner's web page:

Any questions about the map should be directed to staff at the Ag Commissioner's office: 253-4357.

PDF 3/25/11
Trap catches_week ending Mar 25, 2011 (7KB)

No males caught in our traps this week.

However, a scout has reported one male caught on Thursday, 24-Mar, in Conn Valley. The male was still moving when it was found in the trap; slowly, the flight is starting.

PDF 3/24/11
Trap catches--week ending 18-Mar-2011 (7KB)

No males caught in our traps this week.

PDF 3/18/11
Trap catches for weeks ending March 3 and 11 (7KB)

No moths caught last week.

We caught 1 male this week.

As of March 10, we have accumulated 151.89 DDC since January 1, 2011, using data from the Oakville CIMIS station.

Our work with the Degree day model for predictions suggests that we could expect to catch moths of the 1st flight starting around 150 DDC. Trap catches for the next several weeks should indicate whether this is the start of the flight.

It is not yet time to make any insecticide applications.

PDF 3/11/11
Trap catches to date for 2011 (7KB)

Here's an update on EGVM trap catches for 2011:

We caught one moth between Jan 21 and Jan 31.

Since then, we have not caught any additional moths.

We are still waiting for the first flight of 2011 to begin in earnest.

PDF 2/25/11
Industry meetings in Napa (Feb 2011) (126KB)

Welcome to another year of European grapevine moth management in Napa County!

EGVM Industry Meetings to be held February, 2011.  
Sponsored by the Napa County Agricultural Commissioner:

Wednesday, Feb 2, 2:00-4:00 pm at the Rutherford Grange

Thursday, Feb 3, 9:30-11:30 am at the Napa Valley Expo

Friday, Feb 4, 2:00-4:00 pm at the Napa Valley Fairgrounds in Calistoga

Hear results of the 2010 program and plans for 2011. Complete agendas are available using the newsletter link. 

No need to RSVP--just make time to show up and hear about this critical issue.

PDF 1/21/11
Technical Working Group Report--Now Available (50KB)

The Technical Working Group (TWG) on Lobesia botrana met Nov 8-10 in Napa, CA.

They have released their report from this meeting.

The TWG process is primarily a technical/scientific process; domestic and international scientists who are recognized experts on L. botrana are invited by USDA, APHIS to come together and review information. From this review, a set of recommendations is developed and a report written.

This report should not be confused with any policy decisions--these are recommendations based on the best available science.

The next steps are for all parties to come together to prioritize, discuss the recommendations, and decide the most appropriate steps to accomplish what we need to do in 2011, and beyond.  

PDF 12/8/10
Trap catches_3rd flight

Trap counts for week ending 24-Sep-2010. We did not catch any males last week. Looks as if the 3rd flight is over.

PDF 9/27/10
Trap catches_3rd flight

For week ending 17-Sep-2010. We continue to catch males of the 3rd flight.

PDF 9/19/10
Trap catches_3rd flight and PHOTOS

Trap counts for weeks ending 3-Sep and 10-Sep, 2010. We continue to catch males of the 3rd flight. 1st and 2nd instar larvae of the 3rd generation are feeding inside berries. To determine risk to your crop, continue to monitor the Ag Comm/CDFA trap catches in your area, as well as monitoring clusters for damage. Pages 3-5 of the newsletter contain photographs of 2nd generation larvae and berry damage.

PDF 9/12/10
Trap catches_3rd flight

We are revising our timeline for the 3rd flight. The degree-day model projected the 3rd flight would begin on Aug 4. Based on information collected last week, we now believe the 3rd flight started approximately 1 week later than projected (approx. Aug 12.) Please read the newsletter for additional information, and to access the trap summary for the week ending Aug 27, 2010.

PDF 8/31/10
Shipment of grape samples for laboratory analysis

All grape samples (other than petioles) leaving the quarantine area for laboratory analysis must have a Certificate of Quarantine Compliance, issued by the Ag Commissioner. You cannot send grape plant samples out of the quarantine zone without a CQC. Please follow the instructions in the newsletter document to obtain a CQC.

PDF 8/23/10
Trap catches_3rd flight of Lobesia botrana

According to the degree-day model, we should be at peak flight today. Because of the generally low number of moths, and the use of mating disruption, we are not detecting males in our traps. Insecticide treatments should continue to go on as scheduled, based on predicted life cycle from the degree-day model.

PDF 8/19/10
VMB and EGVM workgroup meeting

Next Wednesday, Aug 18, 9-10 am, UC CE meeting room: Area-wide MD program for VMB; impact of Lobesia insecticides on natural enemies; learn to recognize common leafroller natural enemies.

PDF 8/13/10
Trap catches_3rd flight of Lobesia botrana

The 3rd flight is off to a very slow start. We did not catch any moths this week. From the looks of it, our management program is really starting to show an effect. Great job, everyone, keep up the good work!

PDF 8/12/10
Trap catches_3rd flight of Lobesia botrana

We caught our first moths of the 3rd flight today. LATE-harvested blocks should be treated Aug 15-20, at the time of peak egg-laying. EARLY-harvested blocks (conventional treatments) can be treated anytime between now and Aug 20, to comply with PHI. Organic growers will want to begin treatments Aug 15-20, and may have to treat twice if using Bt.

PDF 8/5/10
Trap catches_2nd flight of Lobesia botrana

Very few males were caught this week, signaling the end of the 2nd flight. This flight was likely prolonged by the cool weather. The cool weather and slower accumulation of degree-days also means that the prediction for the start of the 3rd flight has been pushed back to near August 3 (earlier predictions were for Aug 1). Stay tuned for news of the 3rd flight!

PDF 7/29/10
Trap catches 2nd flight

For week ending 23-Jul-2010. Just a few males still trickling in this week as we are coming to the end of the 2nd flight. Stay tuned for word on the 3rd flight, which we are expecting towards the end of the month/beginning of August.

PDF 7/22/10
Projection for 3rd flight of Lobesia botrana

We have used a degree-day model and our European resources to predict the timing and treatment of the 3rd flight. Treatment of the 3rd generation is essential to the regulatory and aggressive management effort in Napa County. All affected areas of the County that were treated during either or both of the first two generations should plan to treat the 3rd generation. Fruit must be protected from 3rd generation larval damage.

PDF 7/19/10
Trap catches_2nd flight of Lobesia botrana

For week ending 16-Jul-2010. We still had a few males trickling in this week, so the 2nd flight has not quite ended. I have also been recovering parasitic wasps from samples of OT (orange tortrix) and OLR (omnivorous leafroller) that have been submitted by growers in Napa. Page 2 of the newsletter contains a guide to recognizing pupae of these parasitoids in the field.

PDF 7/16/10
MANDATORY compliance agreement meetings

The Napa County Ag Commissioner's office is holding MANDATORY MEETINGS to issue compliance agreements to each grower, harvester, hauler or receiver (wineries) of winegrapes within the European Grapevine Moth (EGVM) quarantine area, which includes ALL of the grapegrowing regions of Napa County. You must attend one of the meetings in order to harvest, receive, haul, or move winegrapes from property you own or operate within the quarantine area. See the attached newsletter for meeting dates. You must contact the Ag Commissioner's office to let them know which meeting you will attend 707.253.4357

PDF 7/16/10
Trap catches_2nd flight

For week ending 9-Jul-2010. Trap catches are lower this week. The second flight is ending. See page 2 of the newsletter for graph of the 2nd flight to date.

PDF 7/9/10
Trap catches_2nd flight

Monitoring trap data for week ending 2-Jul-2010. Page 2 contains a graph of catches to date for the 2nd flight. Peak flight occurred this week, as predicted. Concurrent with peak flight is peak egg-laying. Enjoy the (Lobesia-free?) holiday!

PDF 7/1/10
Trap catches_2nd flight

Trap catches for week ending 25-Jun-2010. Trap counts are on the rise. Page 2 contains a graph of the catches to date for the 2nd flight.

PDF 6/24/10
Maps of trap catches

Trap catches are summarized by square mile grid block for the first flight of Lobesia botrana (18-Feb to 2-Jun-2010) in California. I would like to acknowledge the GIS team at USDA for creating the Google Earth layer from which I pulled these maps.

PDF 6/21/10
Monitoring traps_2nd flight

Trap catches for week ending 18-Jun-10. Very few males caught at the beginning of the week. Trap catches started to inch up by the end of the week. This is a slow start to the 2nd flight, as expected.

PDF 6/18/10
UPDATED insecticide list for Lobesia botrana

Agri-Mek (abamectin) has been added to the list of insecticides for Lobesia botrana in grape. Abamectin is a larvicide that may be used to kill older larvae (4th and 5th instar), as well as young larvae.

PDF 6/18/10
Second generation flight has started

We have caught moths of the second generation in Oakville and Rutherford. The first moths of this flight were caught on June 10, 2010. The newsletter contains our predicted timeline of the 2nd generation, and suggested timing of insecticide applications.

PDF 6/14/10
Workgroup meeting

The monthly invasive pest workgroup meeting will be held this Wed, 16-Jun, at the offices of Walsh vineyards managment from 9-10 am. Topics will include EGVM insecticide trials and validation of the degree-day model for the 1st generation.

PDF 6/14/10
assistance FUNDING available to growers battling Lobesia

NRCS is offering assistance for grape growers battling Lobesia botrana in Napa County. Applications will be accepted June 9-23, at the NRCS office in Napa County. See attached newsletter for additional information. Phone for NRCS: 707-252-4189

PDF 6/9/10
Monitoring traps

Trap catches for week ending 4-Jun-2010. No male moths were caught this week. The first flight is now officially over. We expect the 2nd flight to start in mid to late June.

PDF 6/5/10
Summary of trap catches and egg monitoring for 1st generation

Table and graphs summarizing trap counts and egg monitoring for 1st generation. Data were collected and summarized for 4 unique vineyard sites and 2 olive orchards in Napa County.

PDF 6/1/10
Projections for 2nd flight of Lobesia botrana

PROJECTIONS for timing of the 2nd moth flight are based on sampling data from the 1st generation and historical weather data from Oakville. Ovicides targeting the 1st generation should be applied 3 to 5 days after the first male is caught. Larvicides should be applied to newly hatching or young larvae. Projections will be updated weekly, and will be based on field monitoring and weather data.

PDF 6/1/10
Monitoring traps

For week ending 28-May-2010. Males are trickling in at two locations, although numbers are so low that the flight is effectively over.

PDF 5/28/10
Monitoring Traps

For week ending 21-May-2010. Trap catches are very low this week. This flight is ending.

PDF 5/20/10
Egg monitoring in OLIVE

Conducted on May 19, 2010. No eggs or larvae found in olives. No vineyard egg monitoring was conducted this week because all monitoring sites have been treated. The current life stage found in vineyards is 2nd instar larvae. If you have not yet treated, this is still a good time to treat to kill these young larvae.

PDF 5/19/10
EGVM Workgroup meeting

Updates on Lobesia botrana will be presented at this month's Exotic Pest Workgroup meeting to be held May 19, 2010, 9 am, at the UCCE Meeting Room in Napa. Topics will include trapping and monitoring results for both UC and Napa County traps. Also, Lobesia botrana larvae will be available for viewing.

PDF 5/14/10
Monitoring traps

Trap catch data for week ending May 14, 2010. Trap catches are steadily declining. This flight should be ending soon. Traps have been shut down in fields where mating disruption dispensers are deployed.

PDF 5/14/10
Egg monitoring

Monitoring conducted on Tue, 11-May-2010. NOW IS THE TIME TO SPRAY if you have not already. Eggs continue to hatch. 1st and 2nd instar larvae were observed. No eggs were observed on olives this week, so they are not contributing as a main host. See photographs of eggs and feeding damage on pages 2-4 of the newsletter.

PDF 5/12/10
Egg monitoring

Monitoring date: Thursday, 6-May-10. Eggs are HATCHING.

PDF 5/7/10
Monitoring traps

Trap catches for week ending 7-May-2010. Trap catches are much lower this week. It looks like peak flight has passed. This is consistent with our egg monitoring, where we are seeing very few freshly laid (white) eggs at most sampling sites.

PDF 5/7/10
Egg monitoring

I expected to see larvae this week, but my plots were treated with insecticide in anticipation of egg hatch. No larvae yet in untreated plots that are less advanced in growth, although 14% of those eggs are near hatch.

PDF 5/5/10
Monitoring Traps

Trap catches for the week ending 30-April-2010. Trap catches were lower in the olives last week, but still rising in the vineyards.

PDF 5/3/10
Egg monitoring and Photos

Black cap larvae seen in Oakville and 3rd Ave yesterday. Egg hatch to follow soon. See photos of black cap eggs on page 2 of the newsletter.

PDF 4/30/10
Egg monitoring

Egg monitoring on Thursday and Friday, 22 and 23-April. We are very near egg hatch in the early Chardonnay in Oakville. Egg development in Oakville Cabernet is behind. We are finding very few eggs in olives, compared to the numbers that we are seeing in the vineyards. All eggs on olives have been found on leaves, near the veins. We have not seen any larvae in olives or in vineyards.

PDF 4/23/10
UC Monitoring Trap catches

Trap results for week ending 23-Apr-2010. Still plenty of males flying this week, during our first generation flight.

PDF 4/23/10
Egg monitoring

Eggs monitored on Tuesday, 20-Apr-2010. Still no black cap eggs detected, and no larvae seen, even in the most advanced blocks.

PDF 4/20/10
Monitoring trap results_Week ending 16-Apr-2010

Warmer weather means more activity in the traps this week.

PDF 4/16/10
Results from EGG sampling

Eggs werw sampled on Friday, 16-April. Note information in newsletter on Degree Day model. For Chardonnay in Oakville, 65.4 degree-days Fahrenheit have been accumulated since 31-Mar-2010. Egg hatch should occur at 118 DDF.

PDF 4/16/10
Results from EGG sampling

Eggs are developing slowly due to cool weather.

PDF 4/13/10
Monitoring Trap Results

Trap catches of males for week ending April 9, 2010.

PDF 4/12/10
Request for letters from OLIVE growers

We are requesting a 24(c) label for Dipel for control of Lobesia botrana on olive. All olive growers interested in showing support for the 24(c), please send the attached letter with your name and signature to the Department of Pesticide Regulation.

DOC 4/10/10
Egg monitoring on Tuesday, 6-Apr-2010

Egg development was monitored yesterday at sites in Oakville and Rutherford. Eggs at Oakville ranch are developing, but are not near hatch (black cap stage).

PDF 4/7/10
UCCE Open House Field Meeting

Friday, April 9, 2010: Learn to identify eggs of Lobesia botrana. English and Spanish speakers welcome. YOU WILL NEED A HAND LENS or MAGNIFYING GLASS. See newsletter for details.

PDF 4/6/10
Eggs of Lobesia botrana

Egg-laying has begun. Most eggs were found in vineyards with high populations of Lobesia botrana, and at least 4 inches of shoot growth. For EARLY varieties, larvicides could be needed within 7-11 days. LATER varities will likely wait until there is more shoot growth. Next egg monitoring date is Tue, 6-Apr. See newsletter for details.

PDF 4/4/10
UC Monitoring Traps

Trap results for week ending 2-Apr-2010. For graph of male trap catches to date, see page 2 of newsletter.

PDF 4/4/10
Delimitation traps in Napa County

Napa County Ag Commissioner announces that results from the delimitation traps are now online. See newsletter for detailed instructions on accessing trap data.

PDF 3/26/10
UC Monitoring traps

Trap catches for UCCE monitoring traps for Lobesia phenology are posted for the week ending 26-Mar-2010. Note the graph (to date) of trap catches in page two of the newsletter.

PDF 3/26/10
UC Monitoring Trap Results

Trap results for week of 19-Mar-2010

PDF 3/19/10
Insecticide list for Lobesia botrana on grape

developed by Cooper and Varela as a resource for grapegrowers with Lobesia

PDF 3/15/10
Recent article on Lobesia botrana

Practical Winery and Vineyard, Mar/Apr 2010

PDF 3/12/10
UC Monitoring Trap Results

Week ending 12-Mar-2010

PDF 3/12/10
Isomate-EGVM, mating disruption product

Isomate-EGVM received Section 3 registration

PDF 3/11/10
Monitoring and Control of Lobesia botrana

Special meeting of the Carneros Exotic Pest Workgroup: March 17, 2010 from 9-10:30 am, UCCE Meeting Room

PDF 3/8/10
UC Monitoring trap results

Trap results for week ending Mar 5, 2010

PDF 3/5/10
UC Monitoring Trap Results

Trap results for week of 22-Feb-2010

PDF 3/2/10
Napa County TRAPS are being deployed this week

Napa County's trapping effort: delimitation and monitoring traps

PDF 2/17/10
Spanish presentation from Jan 20, 2010

Spanish translation of the Lobesia presentation is now available.

PDF 1/22/10
Presentation from Jan 20, 2010

Lobesia botrana presentation now available!

PDF 1/22/10
Welcome to the EGVM newsletter

Spread the word about the EGVM newsletter for information on monitoring and treatment of Lobesia in Napa County

PDF 1/15/10
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