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 SWD conference 
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Joined: Tue Jan 26, 2010 1:42 pm
Posts: 188
Post SWD conference
I will probably be attending to learn the latest on the spotted wing drosophilia next week:

http://whatcom.wsu.edu/ag/sfc2011/docum ... rOct21.pdf

If there are any questions anyone would like to have asked, let me know and maybe I or someone else will ask them.


Thu Dec 01, 2011 3:31 pm
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Joined: Sun Jan 11, 2009 12:01 am
Posts: 36
Location: S.E. Portland, Oregon
Post Re: SWD conference
We look forward to hearing all about what you learn. SWD hit us bad this year. :evil:


Tue Dec 06, 2011 3:14 pm
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Joined: Tue Jan 26, 2010 1:42 pm
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Post Re: SWD conference
Well, the Lynden Berry Conference meeting is tomorrow (12/8) and so I will have more to say. However, yesterday (12/6) I was in Wenatchee for the Washington Hort Assn meeting and I talked for an hour with Tim Smith (WSU) and a few minutes with Elizabeth Beers (Tree Fruit Research Station). Here is what I gather but keep in mind these are not direct quotes and my misunderstanding could be slightly off:

1. There is an increased interest now in what are called "attracticides" and researchers are looking for exactly what combination of chemicals can attract the SWD to an attract-and-kill site. ...what will make this fly come to a very small spot, shall we say. Already, there is some confidance growing at getting the right alcohols and cider vinegars to be effective at trapping and trapping actually has some kind of success in backyards for the spotted wing varmint. The hope is to now improve on trapping to an actual attract-and-kill site that will be even more effective. (My note: I think I got the general idea here, not sure)

2. Netting is a top interest. Mosquito netting is one of many kinds showing some success.

3. The good news is that for crops like blueberries that if you are an organic backyard person and you know how to time it right you only need to apply the organic spinosad product one week in advance, give it a 3 day PHI and then you have 4 days in which to get everything picked. You also have to put in even more insecticides around the perimeter and the reality is that blueberries don't all ripen at the same time and rain can mess things up.....but at least we know that for NON-commercial growers that don't have to have 100% control, it might be good to only put on sprays near the ripening time as this is the time that SWDs start to become active. (My note: I personally would rather rec at least two sprays, starting 2 weeks in advance because I know most homeowners don't really know when their fruit will ripen).

4. We don't know why SWDs were more harmless in 2011 than in 2010 and came out in smaller numbers. The first postulate is the sub-freezing night or two in November of 2010 did them in.

5. We don't know why Hawaii has SWDs but not much danger to the fruit from the SWD fly.

6. The research on parasites for SWDs is so far proving to be worth considering but not currently exciting.

7. GF120 NF can reduce the population but there are enough problems so as to not generally recommend it for home-owner. (for example: finding it in small doses)

8. Problems with parasites in compost bins? Simply cover the bins for a while and hope to get the heat up.

9. So far, Washington grapes have not been bothered, unlike California grapes. Cross your fingers, be nice to your neighbor, and hope for good karma on that one. (Okay, clearly this last sentence was made up by me).


Wed Dec 07, 2011 2:41 pm
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Joined: Tue Jan 26, 2010 1:42 pm
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Post Re: SWD conference
I meant to say for #8 "problems with Spotted wing drosophilias from compost bins? Simply cover the bin for a while and let them die in the bin." At least, from what I understood of Tim Smith he didn't see why compost bins had to be a big problem or understand the worry some have that these bins are (especially with fruit in them) actually a breeding ground for the fly. But then I don't know that Tim has his own compost bin.

The reason I may have used the word parasites is because I heard from a master gardener in Hawaii that with one of the flies that they have a problem with she puts a special screen on her compost bin that has a large enough mesh that the parasitic wasp (? or other insect?) for that fly can come and go to the compost bin but the mesh is fine enough that it will not allow the fly itself to escape.

But with only preliminary results and not fully satisfactory, we still do not even have a definite parasite for the SWD and so my idea there is not even at a testable stage.


Wed Dec 07, 2011 2:49 pm
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Joined: Tue Jan 26, 2010 1:42 pm
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Post Re: SWD conference
12/8/11 New post: okay, I went to the meeting today in Lynden for the Small Fruit Conference....I don't have anything earth-shattering about SWDs to reveal but maybe a few points....I'll try to start off with ones that may be more relevant. Please note that most of these ideas apply to backyard growers as the sense I got of things was that essentially no one could succeed in being organic and commercial for small berries in Western Washington due to the restrictions on number and types of sprays to be certified organic (or very few could succeed). so again, most ideas are for the backyard grower that will be happy if he/she gets high percentage control and can still go organic:

1. The best speaker there was Amy Dreves of Oregon State University. She pointed out to me that she is working to see at what temperature you could take care of the problem by simply putting the fruit in, say 1.7 degrees Centigrade refrigerator immediately after picking. Pick the fruit at ripening stage and pick regularly and immediately refrigerate for 72 hours. This may kill all the larvae and you would never notice the problem. She is working on the details.

2. Someone suggested that there seem to be more SWDs found at the borders of the orchard, particularly (I think?) at the early stages. Sometimes shade cloths with pyrethroids might work.

3. Dr. Tanigoshi of WSU Mt. Vernon has been working with the organic chemical Success with some sucess and with neonicotinoids and with malathion (synthetic). Malathion works really well and leaves a residual for several days. He, like most people, would love to see organics work ideally but thinks that right realistically now some sort of rotation of sprays is what is the most effective. He has also been working with other synthetics, such as Lannate.

4. Many people seem to think there may be some promise in the use of backyard gardeners using mass trapping. Apparently, where labor is cheap this is done in places like China already. While the researchers are currently using apple cider vinegar as the attractant for their trapping, the reality is that what many researchers are finding the most effective is yeast and water and sugar. (exact recipe perhaps to be shared later). One researcher got as many as 16,000 flies in one of her yeast traps. Think of that. 16,000. Trapping, if done right, might actually work. Yeast traps are sticky, gooey and messy but the most effective for the masses.

5. One hobby enthusiast wondered how cherry juice would work as an attractant.

6. For studying the larvae after the fruit is infected a mixture of salt and sugar and water was suggested to be placed on the crush larvae to see how many larvae will swim on the surface and can be counted.

7. England and Germany are starting to worry about SWDs....some of the European countries are studying mating disruptors and are also studying the cues the fly may respond to, including olfactory and auditory cues. They are worried because they have even less of an arsenal of insectides to use before the fly adapts to it and co-opts any spray effectiveness.

8. There seems to be some progress made in coming up with Degree day models for the spotted wing fly......like with so many other insects where such has already been developed.

9. Believe it or not, it appears the researchers aren't even quite sure yet how this bug over-winters, though. What they do know is that while there might be a lot of them around now in early December, give it a few sub-freezing nights and the numbers of SWDs dramatically decline.....with females surviving the winter more often than males.

10. Screens on top of the traps, red colors, things like that are helpful for identifying the ideal trap. Trap design may have some importance and is being worked on.

11. Some berries are attacked by the SWD and some are not. The Himalayan blackberry is the most significant problem host. Even salal is attacked. Red Elderberries are badly attacked also.

12. Some think sanitation is helpful. (personal editorial note: I wonder why, though....if you have wild blackberries everywhere, then what is the point of sanitaqtion?).

13. Neem oils don't work. Other oils don't work. Mixed answer on neonicotinoids. Pyganics don't work.

14. Some success with screens .98 mm or less in mesh size. Some researchers working on this.

15. Trellising some of the blueberry varieties, particularly droopers like (Blugold?) are useful to reduce droppage and are also useful in terms of helping the orchard to assimilate the sprays and help for spray effectiveness.


Thu Dec 08, 2011 9:44 pm
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Joined: Sun May 15, 2005 10:57 am
Posts: 1375
Location: Portland, OR
Post Re: SWD conference
Great post, Don,
Thanks for sharing the information. It's good to know what works, what probably works, what might work, and what doesn't work. And what we really just don't know.
John S
PDX OR


Sat Dec 10, 2011 8:28 pm
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Joined: Sun Jan 11, 2009 12:01 am
Posts: 36
Location: S.E. Portland, Oregon
Post Re: SWD conference
Thanks for going to these conferences and sharing with us. I look forward to hearing more about the yeast trap recipe.


Sun Dec 11, 2011 2:02 pm
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Joined: Thu Jan 27, 2005 11:27 pm
Posts: 1166
Location: Yamhill County, Oregon
Post Re: SWD conference
Agreed… thank you, Don.

Folks will often ask, “how do you know so much fruit?” -- Because I read the Home Orchard Society’s Forum – which includes fine research like yours.

_________________
Temperate Orchard Convservancy: http://www.temperateorchardconservancy.org/index.php


Sun Dec 11, 2011 10:50 pm
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Joined: Tue Jan 26, 2010 1:42 pm
Posts: 188
Post Re: SWD conference
I forgot what my friend Marilyn Tilbury is using for her yeast/water/sugar mixture as a bait, but one researcher uses the following (and I think Marilyn is somewhat similar)

"one 2.5 oz packet of yeast + 4 teaspoons sugar + 12 ounces of water distributed in four or five Mason jars were very effective in monitoring and evaluating infestation levels of spotted wing drosophila."

http://www.rinconvitova.com/spotted%20w ... ontrol.htm


There seem to be a lot of researchers that know the yeast attracts even more SWDs....I guess because yeast is a key food sought for by the SWD. I asked one of the researchers why the yeast traps were not then used for trapping for the data he collected and he said it was because the yeast mixtures were a more opaque, slimy, messy business.


Also of note is that Colleen Burrows was doing a day by day trapping/mapping of the SWD last summer for the state of Washington

http://whatcom.wsu.edu/ipm/swd/scouting.html

If she does this again for the summer of 2012 then perhaps her data could be somewhat useful (that is if Clark County Washington is similar enough to Portland area). If so, bookmarking the previous link may prove useful.


Wed Dec 14, 2011 7:22 pm
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