I have Tayberry and Obsidian Blackberry that ripened early enough to avoid their presence,but found some in Chester and Triple Crown.They come around here in late July into August and really go after the wild Himalayan Blackberries at that time.
Their ovipositor must be fairly tough to pierce a Fig fruit. Brady

Up here in vt, what you outline is the recommended strategy....go early with the soft thin skinned fruits. Certainly that has played out for our plantings.
We have abandoned fall raspberries, and late season blue berries are a crap shoot. So far no problems with June strawberries, early raspberries and early blues.
But we may get a much more significant winter knockdown than you in va. Not sure if that approach will be equaly effective with a mild winter.

Thanks for the feedback. It confirms what I thought/feared.

I'll probably put in a couple of Anne and Polka Raspberry plants and hope they don't find me right away, but I'll put most of my effort into the Prelude and Polana. I'm hoping the Sunshine Blue may still be okay if they're mostly done by early July, but I'll definitely give up on the everbearing strawberries and just go with the Junes.

It does sort of make me wonder about adding Romeo Cherries to the Carmine Jewels I just planted. I wonder if they would be too late?

It is sort of sad, but probably better than being disappointed later if all my effort just becomes fly food.

My concern is that the SWD will broaden its peak population season to include May and June, as temperatures then are warm enough. But for the next several years, early crops may be the answer.

Here in Madison, our raspberry patch began to yield ripe fruit in August, and the berries were free of SWD until mid-September. Then the crop was infested, and I was getting ready to cut down the entire patch, when we had two or three cold nights in a row, not quite cold enough for frost. The SWD was eliminated, and we started to see ripe raspberries that were free of larvae. This continued until the season ended in November. Our blueberries typically turn ripe between July 15 and August 10, and so far, they have been unaffected by SWD. I am not sure how long this will last.

Hmmm... so maybe there is hope for good fruit late fall if they get zapped by the cold. Good to know.

And here in Virginia and some other places, they are now also finding African Fig Fly, which is another type of drosophila. That wasn't what I saw on the Celeste fig, but they appear to be another potential menace in the making.

You must have gotten pretty cold to zap them. I still saw them until at least late October. After that, there wasn't too much left for them to attack, other than a few stray raspberries and some Prime Jan blackberries.

They've hit me in early August for the last two years, so the 2nd half of Triple Crown is badly affected, along with all the primocane raspberries. None of the floricane raspberries have seen any damage. Even the late season Royalty (floricane purple raspberry) was unscathed.

So, this winter, I'm removing a lot of my remaining primocanes and replacing them with floricane raspberries. I'll be removing all the Caroline and Autumn Britten raspberries and most of the Prime Jan raspberries. I'm keeping most of the Prelude, even though it has a sizable fall crop which gets infested. I'm also keeping Anne (yellow), my best tasting variety, which seems less hard hit than the others.

In their place, I'm planning to plant Lauren (early season) and Taylor (late season). From Nourse's website, it looks like Taylor will have about the same season as Royalty. Hopefully it will have more flavor.

They hit my primocanes (Heritage,Caroline, and Preludes) hard about first of September and ruin entire crop. Cold weather in October didn't help here in WPA.. Not sure anything can be done in the future.

SWD infestation is causing me to think more kindly of winter weather. Right now we are having unusual cold weather for November, more like the weather we would expect in January. Daytime highs are around 18 degrees F, and it gets down to around 5 or 10 degrees at night. This should kill the SWD eggs that might be in someone's compost pile. With regard to compost, we have an open pile, and I no longer put fruit peels or watermelon rinds on the pile, during the spring or summer months. We still compost leaves and twigs, grass clippings, and weeds. But no rotten fruit.

Would it help to cover them with the thinner version of floating row cover in late July, or would that interfere with pollination? Or could one hand pollinate a few bushes and then cover them with the floating row cover? Would they get too hat with the row cover? Or how about some mosquito netting? I only planted some raspberries this past June, and have some blackberries on order for spring, so am wondering how to get to eat them. Northwoodswis

I have the SWD problem from late July through September. By October the SWD seem to diminish in numbers. My Fall raspberries are easily ruined and turn to mush but the Prime Ark 45 blackberries I have seem to fair much better. I think it must be the thickness of their skin that seems to inhibit the berry from turning to mush as quickly. My rule of thumb is if the berry isn't leaking, then I'll eat it. I have gotten over the thought of eating their eggs and larvae.

SWD are so small and numerous, I think it would be tough to keep them out with netting unless you had a greenhouse. After watching them this year, I wonder if someone were to develop sticky fly paper treated with an attractant, that you might be able to reduce them considerably with something like that if placed in reasonable numbers around your plantings.

I have this forum to thank for my big raspberry crop this year, the bushes were here when we moved in and all I ever did was trim them. after doing some reading here and at the CSU website I cut the canes to the ground in late winter, fertilized, let them take over a little more of the lawn. No early crops but we got a very big fall crop from late August until the first few days of November. Easily five times more berries than last year's two crops combined.

But the bad news is that I read about SWD too, and the berries were infested from the first we picked in late Aug until mid Oct. Probably I wouldn't have noticed the little worms, or I would have thought they were just an overripe berry or two and discarded the ones with obvious worms. But when you soak the berries and look closely a lot of worms come out. We still ate them but I didn't want to give any away to friends.

jtburton,
Great idea. Maybe take some cloth strips, dip them in berry juice, then smear on sticky-trap. It's worth a shot, anyway. Do these flies have an all-time favorite fruit? Another idea might be to put some ripe fruit inside one of those electric bug zappers.
Northwoodswis

I remember Axel,from California,who posts here sometimes,but more on Cloudforest,reported that the Raspberry was the main attractor at his location. Brady

Raspberries seem their primary target in my yard, though blackberries also get hit pretty badly. I've seen them on Elderberries a bit. I haven't noticed them on the blueberries, but most of those end up in a bird's belly, not mine, so it's hard to say.

I've been thinking about the bug zapper idea as a way to deal with other pests. For instance, if we can figure out what PC is attracted to and put a few around the orchard in May, then maybe we could eliminate/reduce the need to spray...

If you put ripe (or overripe) berries in during august to catch SWD, you may zap some yellow jackets as a side benefit.

I don't know if honeybees would also be attracted to ripe fruit. It sounds like the SWDs are smaller, so maybe a hardware screen around the trap if it proves to be a problem for the honeybees. I have heard that one can kill wasps with a dish of sugar water with borax in it. Might that work on the SWDs if one used fruit juice and borax? There must be a natural way to outsmart those little buggers!
Northwoodswis

Apple cider vinegar is often used to lure SWDs. I've caught 1000's that way, but hundreds or thousands more ended up in the fruit and not the vinegar trap.

I see that I am about 9 yrs late to this discussion, but SWD doesn’t “go away” with standard cultural practices! And some of the questions here are still very relevant to home gardeners seeking an organic path to growing berries and fruit.

So I am happy to report on my successful experience with a biological control organism that can effectively control SWD on raspberries and other fruits. I applied this soil-based predator, the beneficial nematode Steinernema feltiae (Sf) to my western NC raspberry beds in 2016. and for the last six years I have seen no SWD larvae on the fruit!

This beneficial nematode is easily applied by a soil drench to the growing beds. And it can be used to treat a growing area of up to an acre for less than $100. (Sf is available from several beneficial insect sources, such as Arbico).

Never too late to contribute to the SWD discussion, and any control news is welcome.

from

https://www.goodfruit.com/nematodes-vs-swd/

"S. feltiae caused a significant reduction in SWD adult emergence in both lab and field trials, though the effect in the field lasted about two weeks past the application date, after which SWD numbers went back to their previous levels."

...and other studies showed certain Bt species were more effective than S. feltiae, and were highly dependent on soil temperature. Another difficulty is the high variability of home gardeners caneberry patch soil surface: weed or grass cover, compaction, etc.

I hope that other people could repeat your excellent results. Here, I think annual fly-ins of SWD (as opposed to in-ground pupae from the previous year) from neighboring sources would result in more-than-zero SWD on the fruit.

Yes, I was surprised by the extent and duration of the control effect! I had read that S feltiae was known (in the commercial literature) as a predator for Drosophila. But such extensive suppression of SWD and for multiple years?? In considering the question of why Sf was working so well, I came across the literature on the IPM double-barreled "attract-and-kill" strategy for SWD, sometimes pairing chemical and biological products to stop the SWD reproductive process.

And it occurred to me that after Sf application, the fruiting raspberries offer an intergenerational “attract-and-kill” method in which SWD breeding adults are attracted to deposit their eggs in the ripening berries. Then the next-generation SWD larvae which fall to the ground are parasitized by the beneficial nematodes. And the Sf reproduction #'s are amazing - thousands of Sf larvae for each parasitized SWD larva.

The protection of nearby untreated fruits, in my case blueberries and figs, was also a surprise, albeit a pleasant one. But if raspberries serve as a SWD "magnet" for feeding, maybe Sf can knock back the infestation levels for other fruit crops which don't reproduce on the ground!

That is a pretty exciting hypothesis, but just a hypothesis from a single case study. So as you note, we definitely need more field trials to generate knowledge about the roles Sf can play in SWD control. And that should be a great opportunity for interested home gardeners.