Maggots in the blackberries -- blech

[bcday]

I've been picking wild blackberries from a small patch here for a week or two now. Yum! But a few days ago I filled a sandwich bag half-full of berries and left it on the counter for the afternoon, then put it in the fridge overnight. When I took it out the next day, the berries were crawling with fruit fly larvae! Well, even a fruit fly can't grow from an egg to a 1/8" larva overnight at 37*F. I hadn't seen anything wrong with those berries but the larvae must have been in there somewhere.

I picked some more berries, rinsed them, put them in a container with some water and a pinch or two of salt, and waited. In less than an hour little white larvae were poking out from inside the berries and floating around in the water. I took yet another bag of fresh berries to Cornell's extension service and the folks there are going to let the larvae hatch out so they can get a good ID on the adults. But since these berries are in otherwise good condition, just ripened and not overripe, deteriorating, or damaged, the folks at the extension service feel sure that the culprit is the Spotted Wing Drosophila -- an invasive species of fruit fly from Asia that hasn't been confirmed in my county yet and wasn't seen anywhere in NY until 2 or 3 years ago.

The fruit flies we usually see only feed and lay eggs on overripe or damaged fruit. This spotted wing fruit fly inserts its eggs into healthy undamaged fruit that is just ripening and is in prime marketing condition. People picking or buying the fruit can't tell that it is infested just by looking at it. I'd been eating fine-looking berries from my own yard and wouldn't have known anything was wrong with them if I hadn't had that bag of extra berries sitting around.

I tried the salt-water treatment on a few of my fall-bearing red raspberries that are just starting to ripen. Yep, baby fruit fly maggots no more than 1/16" long in those too.

If you are picking or buying berries, any kind of berries, at this time of year, try soaking a few in salt water for an hour or so before you eat any. A teaspoon or so of salt to a cup of water is plenty to get any little white wigglers irritated enough to poke their noses out.

[shelleybean]

Oh, yuck!

I'm having a small cookout tomorrow and one of the easy things I planned was a spinach and berry salad with strawberries, blackberries, blueberries and raspberries. I'll check these berries. Might need to change my plans. Thanks!

[habitat_gardener]

Those tiny maggots are the reason I pulled out my blackberries (prolific but not that good) 2 years ago and my raspberries (wonderful but I couldn't eat them once I knew they were full of maggots) last year. They were first observed in Calif. in 2008

[FarmerShawn]

Somebody was warning me about these little buggers, and indicated that they can infest tomatoes just as well as berries and other fruit. Anybody know how much we need to worry about our tomato crops?
Shawn


There are more things in heaven and earth than are dreamt of in your philosophy.

[habitat_gardener]

Originally Posted by FarmerShawn

Somebody was warning me about these little buggers, and indicated that they can infest tomatoes just as well as berries and other fruit. Anybody know how much we need to worry about our tomato crops?...

Your local ag extension should know if they are in your area yet.

When they were infesting my blackberries, it was pretty obvious. The variety I grew was not palatable until it was very very soft, so there were lots of fruit flies around the fruit. However, I didn't know about the maggots until someone at the community garden mentioned them.

One website said their favorite fruit is cherries.

[noinwi]

Oh great! I have a couple gallon bags of(Himalayan) blackberries in the freezer and have been eating them as I pick! Friends have come over and picked gallons too. I guess tomorrow I should pick a small batch and salt-water test them to see what I've been eating.
I have noticed some maggots in some rose hips that I picked, but with those, I can just cut them open to clean.

[bcday]

I set vinegar traps under my blackberry and raspberry plants over the weekend and caught some adult fruit flies. I took them up to the extension service and the folks there confirmed that the females had the serrated ovipositor that is characteristic of the Spotted Wing fruit fly. The serrations help it to cut through the fruit skin to lay eggs inside healthy fruits. Our common fruit fly doesn't have this saw-toothed feature, so it can only lay eggs in fruit where the skin is already broken from being overripe or damaged.

Now I have to decide whether I want to get rid of the berry plants or try to keep these new fruit flies away from the ripening fruit. Grrrrr.

Spotted Wing fruit flies have been found with Himalayan and Evergreen blackberries in the PNW. They also infest a number of other fruit crops.

[bcday]

I think that since this Spotted Wing Drosophila doesn't seem to bother unripe fruit, maybe I can put a bag over an unripe cluster or wrap floating row cover material around it and secure it with a twist-tie.

The only problem with that is that not all the berries in a cluster ripen at the same time, so harvest would involve a lot of wrapping and unwrapping at every picking.

[tjg911]

i was going to suggest a frc but i question if it will work, here's why. i have a harry lauder walking stick plant and the japanese beetles in the past have eaten all the leaves and threatened the plant's survival. this was so serious that one year i wrapped it with frc but they managed to get probably at the base. it is really hard to seal it off if you don't bury the edges. fruit flies are a lot smaller than j beetles. perhaps if you tied it at the base with rope or jute?

tom

[bcday]

Covering the whole plant with floating row cover and burying the edges is one of the suggested controls. Just for this season, because there's so little of the season left, I thought I'd try wrapping just a few unripe clusters and see if frc can keep the flies out before I cover the whole berry patch. I think I can tie the frc tightly enough at the base of the cluster to keep the SWDs out.

[noinwi]

This morning I picked a cupful of BBs and put them in a bowl of salty water for an hour or so. I saw nothing but plant material...no wriggling or white things, so I went out a while ago and picked another quart for a crisp and I have them soaking now. I'll let you know how it goes a bit later. Maybe the garden and jumping spiders are keeping the pests under control or maybe it's just a good year. I haven't heard anything bad from the friends that picked a ton of berries a few weeks ago. Keeping my fingers crossed!

[noinwi]

Oh, and these are just wild invasives(Himalayan)that have taken over our wetland acreage(it hasn't been maintained for several years). There are acres of wild roses too in addition to(too)many rugosa roses that were planted here years ago, so maybe the flies are attracted to other fruit at the moment.

[noinwi]

Nope, no wormies, just one tiny spider I had to rescue. Went ahead and made my crisp. I feel better about eating all those berries while I was picking!

[clkeiper]

We have them, too. They have destroyed the entire raspberry crop so far. The only available control that is reasonable (but isn't listed on the label) is spinosad sprayed every 5 days (as long as you aren't selling the berries, otherwise you have to use something called Delegate and it is over $200.00 /20 oz). or malathion every 7 days, but you can be certain they are in the crop if as you pick them the berry is all mushy and collapses. VERY disheartening to try to harvest.

[bcday]

I cut down all the fruiting canes from the blackberries and treated the clusters of fruit to a long soak in a bucket of soapy water, followed by an even longer soak in 1:20 bleach:water solution before bagging them up to be taken to the landfill.

Hopefully that will at least cut down on the number of the little bastids that will be overwintering here.