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Post by Admin on Aug 27, 2013 16:11:33 GMT
From:
"Doug Pfeiffer" <dgpfeiff@vt.edu>
Date: Tue, Aug 27, 2013 9:33 am
Hello all,
Ben raised a good point - the main point of spraying is to keep adults from laying eggs. We have no measure to get the larvae once in the berries. Danitol does provide some control of mites, as does bifenthrin. But this is short term control - like the other pyrethroids, they are very toxic to predatory arthropods. You may still see a flare-up of mites, though delayed. Use of pyrethroids may be needed for SWD in sensitive varieties, but the whole vineyard may not need to be treated. We clearly need less disruptive controls. I am testing some new chemistry this season that should fit much better into an IPM program, and have also started a graduate student to start work on biological control of SWD. Planning our first field trip today!
Doug
****
"Doug Pfeiffer" <dgpfeiff@vt.edu)
Date: Tue, Aug 27, 2013 9:51 am
Dave,
This would be interesting to look into. We are doing similar work with brown marmorated stink bug. It would be tricky because if not killed, the flies could move into the crop to be protected. But we may need to put together a muti-pronged approach including tactics like this to help prevent resistance to insecticides.
Doug
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Post by entomologyShrader on Aug 27, 2013 16:21:22 GMT
A note on trap cropping: This works best for insects that are spending a majority of their time on the exterior of the plant. However, the economically damaging stage of the SWD is the larva, which are on the interior of the fruit. You would have to target egg laying females before they laid eggs into the fruit. Otherwise you are providing a very good food source (caneberries) for SWD located right next to vineyards. This may cause an unintended SWD population explosion in caneberries that may hop over to the grapes.
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Post by robbie on Aug 27, 2013 16:29:18 GMT
So I sprayed the Nebbiolo block with Malathion yesterday. The block is located near the top of a mountain on south westerly facing slope along a wood line. Shade persists on the top rows of this block well into the morning. There is also a light amount of deer damage in the first several rows.
I went for an inspection this morning to find the swd flies still VERY active in the first several rows. The spray seemed to have some effect in the lower rows of the block. I could still smell the Malathion in the air.
There are several hypothesis I have regarding this experience.
A. The malathion only has limited to no effect.
B. The malathion has strong effect, but the damaged fruit was enough to continue to attract more flies.
C. The malathion has a strong effect but the proximity to the wood line also created a proximity to additional flies that were not around during the spray.
D. The malathion does not have a strong residual, despite the odor being still prevalent.
I will be spraying again tomorrow with Mustang Max.
Please let me know your thoughts.
Robbie
Breaux Vineyards
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lucie
New Member
Posts: 2 
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Post by lucie on Aug 27, 2013 19:45:31 GMT
Trees are the greatest "disease" of all! That said probably all of the above.
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Post by martha on Aug 27, 2013 20:12:17 GMT
Cornell University has a paper "Chemical Control of Spotted Wing Drosophila in Berry Crops" (not specifically grapes). They suggest Assail or some other neonicotinoid in addition to the other standard rotations of Delegate - class 5, Mustang Max - class 3A and malathion - class 1B. I talked to an Assail technical rep. He said Assail is not the best for adults but it is systemic and will kill the larvae that are in the berries. It can only be used two times a year. It has a 3 day PHI. The sales rep said honestly Mustang Max is better on adults. Assail is a 4A class, same as Belay. We don't want to use Assail yet, with it's limit on twice a year, and hope (!) we don't have to.
Since Tombstone and Mustang Maxx are in the same class and similar in price, maybe it's the 1 day PHI on Mustang Maxx that is attractive?
We are concerned that malathion can only be used twice, and Delegate 5 times. It's a long way off until harvest of cab franc and petit verdot and cab. sauv. We've been spraying once a week.
Martha
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Post by martha on Aug 27, 2013 20:20:23 GMT
P.S. The Delegate tech rep said a product like Cohere (soap sticker and spreader) is a good idea for Delegate. Mustang Maxx tech support said Cohere is not a good idea but a spreader, not a sticker, could be used. Malathion rep said do not use Cohere.
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Post by Frantz Ventre on Aug 27, 2013 22:00:48 GMT
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Post by robbie on Aug 28, 2013 12:45:03 GMT
Hi Everyone,
I posted yesterday, but I am not sure it worked. I sprayed two days ago on Monday afternoon in our Nebbiolo block. The block is at the highest part of the vineyard on a south west facing slope. Just east of the block is the top of the mountain and a tall mature wood line. The top 6 rows or so of the block remain in the shade for a good portion of the morning.
I found deer damage in the block on Monday morning, and of course with animal damage I found fruit fly infestation. The bulk of the flies were SWD. I decided to put on a malathion spray that afternoon on the entire block.
I returned the next morning to find a considerable amount of SWD still hovering around the fruit in the upper 2-3 rows. Lower down, there seemed to be less, but it was impossible to know for sure. I came up with several hypothesis regarding this experience:
A. The malathion was not very effective.
B. Although the malathion was effective, the attraction of damaged fruit drew more SWD despite the persisting smell of the malathion Monday morning.
C. The malathion was effective, but provided little residual other than smell.
D. The proximity to woods,late persisting shade, and cool upper elevations offer too much of an attraction to SWD and they therefore continue to move to more attractive areas.
Yesterday afternoon, I revisited the site around 3 pm to see how the heat changed the presence of the SWD. They were very difficult to find, even in the damaged fruit areas. This lead me to believe the best time to spray for the SWD may be early to mid morning when they are most active. It could also have meant that it simply took some time for the flies to die off.
This morning August, 28 I revisited the site again. Unfortunately, it is raining and I imagine that the flies would be less active even before arriving. I had difficulty location any, but there were definitely more,even in the rain that there were yesterday afternoon.
I will do a follow up spray tomorrow, rain permitting at mid morning for the block using Mustang Max.
Please let me know your thoughts.
Robbie Corpora
Breaux Vineyards
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Post by robbie on Aug 28, 2013 13:38:36 GMT
Thanks Franz...good stuff. Particularly the second article. Perhaps post harvest trapping could be a good idea.
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Post by Admin on Aug 28, 2013 17:53:23 GMT
Don't know if it is the cooler/damp weather but SWD were out in numbers this morning, when yesterday none were around except in one small area which we spot sprayed.. we are at about 20.5 brix, planning on harvesting early next week. Spraying Malathion as we speak between rain bursts.. no other alternative, can't wait till it is dry, as they are laying eggs in the rain. Be extremely diligent the weeks leading up to your harvest and stay on top of new populations. This is going to be a challenging few days. I have heard of decimation of fruit in one vineyard. Hopefully research can come up with something soon.
My observation is they are most active early, early in the morning, in the couple hours post-daybreak. If you want to get an accurate population count, this would probably be the best time, and the best time to spray.
Robbie, my humble guess would be the Malathion seemed less effective due to the larvae hatching and re-populating the fruit area. Unfortunate that nothing kills the larvae presently, to my understanding.
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Post by davemrv on Aug 28, 2013 23:48:46 GMT
I wonder if when people post that they sprayed for SWD if they would not their speed, amount/acre, what type of trellis and what they used, since some have had malathion to work and other haven't had any success. I just think for data collection this work help. It may be coverage is very important to get good activity. I say this cause I have some Chancellor that is GDC and is taking a large hit from SWD but then my PN and Chancellor 800ft away on VSP has very little damage.
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Post by robbie on Aug 29, 2013 12:25:05 GMT
Second SWD spray is going down in Nebbiolo this morning. This time we are spraying closer to day break. It is still damp and overcast. This mornings inspection turned up a good infestation of fruit flies, but not as heavy as Monday morning. The lower rows, farther from the wood line are still much less infected.
I sprayed just under 3pts/acre of Malathion on Monday. Today I am spraying 4 ozs/acre of Mustang Max. The Nebbiolo is on lyre, and I am sure lyre is close to as bad as GDC with regards to shading and is therefore a pretty ideal candidate for infestation. That being said, although I have spotted SWD in other blocks, Merlot on Lyre, and Cab Sauv on VSP, the spottings are rare and seem to be a similar level of infestation. I would guess that GDC and Lyre lead to probelms of spray effectiveness, but variety is more of a determinant about where they infest and how much...
Robbie
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Post by robbie on Aug 29, 2013 17:21:45 GMT
1 pm inspection showed no flies in the treated rows of Nebbiolo. Mustang Max appears to work well, the residual is now the next question.
Does anyone have any pictures comparing the common vinegar fly and the female SWD? Also, I am looking for pictures of SWD larvae to compare to pictures of common vinegar fly larvae. I realize that there are a number of different growth stages, even as a larvae, the more the pictures of each I have the better.
Thanks
Robbie
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Joseph P. Reed, FMC Tech Rep
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Post by Joseph P. Reed, FMC Tech Rep on Aug 29, 2013 21:36:52 GMT
Greetings,
I'm the Technical Service Rep for FMC and was forwarded this link. Here are my comments on SWD situation, as I have dealt with SWD in the Carolina's, Michigan, Ohio, New York, Pennsylvania, New Jersey,and Points North in Blueberries, Cherries, Plum, Raspberries, Strawberries, and Grapes.
1. Controlling adults is KEY to control fruit damage.
2. Once the egg is laid in the fruit, the fruit is damaged, PERIOD.
3. Neonicotinoids have not shown economic control of SWD larvae in small fruit.
4. A Non-Ionic Surfactant, such as Cohere and others, is satisfactory to use with Mustang MAXX, HERO, and Brigadier insecticides.
5. HERO (bifenthrin + zeta-cypermethrin) and Brigadier (bifenthrin + imidaclopralid)currently have longest residual activity against SWD, followed by Mustang MAXX and last is Malathion at 1 day. Mustang MAXX has excellent knockdown of adults and good to excellent residual control; HERO has excellent knockdown and excellent residual control.
6. Be prepared to go on a spray schedule to control this insect. I am seeing intervals as tight as 4 days in blueberries, raspberries and blackberries, and up to 7 days in plums, of course this is based upon when the first SWD are trapped. As the grape berries begin to ripen is when the SWD will be most attractive to SWD.
7. Grape variety / Cultivar will play an important role in the intensity of SWD control programs.
8. Another more immediate concern is the Pre-Harvest Interval (PHI)of insecticides. For Grapes, Mustang MAXX has 1 day PHI; HERO has 30 days PHI; Brigadier has 30 days PHI.
I hope this helps, and stay vigilant.
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Post by davemrv on Aug 29, 2013 23:39:45 GMT
How has results been with delegate? Dr. Pfeiffer had recommended it. I know everyone is having good luck with Mustang Max, but given how fast SWD can multiply how many sprays are get going to have before it? I used Py-ganic Wednesday, it works well to knock down what is there but does nothing for residual. From what Joseph said it looks like we need to use Brigadier when we first see SWD and then py-ganic and mustang-max near harvest.
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