Sounds like Raspberry Beetle to me. It can be controlled with a pyrethrum spray, but does hang on from one year to the next. Get rid of it otherwise it will escalate into a bigger problem.
I prefer Compost tea sprays for all my garden bugs, works for me.

Thanks beeman; So if I get some Pyrethrum spray do you know if it's something that I apply now while the berries are there and is there a spray program more-or-less? Is it your opinion that this years crop is a total loss, or do yu think I could spray and then still harvest those berries that have yet to mature?

Thanks!!

Jowager: I too have the (possibly) same critters in my Caroline fruits, they didn't show up until about a month or so ago. Since all our fruit is harvested and made into juice and there are very few of the worms, I could care less. There is a pretty significant amount of damage to the fruit now but not enough to ruin it for my purposes. I just pick slow and pitch the fruit with a worm hanging.

Thus far, I have not tried to control the little buggers, mybe that will be a mistake in subsequent years. If you do spray, make certain first that there are no pollinators out and working over your flowers, assuming your plants are still flowering as mine are. Picking yesterday evening there were many wasps and even honey bees busy feeding off the berries that the worms damaged, guess everybody is storing up for winter.

michael357; That's just it, I have hoards of various pollinators from honey bees to bumble bees to mason bees, great black wasps, really small bees, wasps, moths, etc.

I haven't really seen a single worm on the outside of the fruit. But once in the house looking at them after a quick rinsing, I see a very very small thread-like yellowish whiteish tiny tiny worm on the inside of the berry near the bottom. So if I split the berry open I can see him swimming around in the juice.

It's rather disgusting - and if I don't get a fix on this pronto my wife won't eat another berry ever, let along give a few quarts to our adult kids and our grand-kids.

What is maddening is that the berries can look totally healthy, kinda firm and all that jazz, then upon closer inspection we have visitors!

Man I built the coolest trellis too....

I'm just sick and depressed!!!!!!

This is a case of timing. If you spray during the day you'll kill off the pollinators, don't spray and you'll get the worms. They come from eggs laid in the flowers.
The answer is to spray when there are no pollinators around.
Dull rainy days they don't fly, or better still evenings just before dark.
As a beekeeper, you'll have to trust my experience. There is a time just before dark when you can see but the pollinators are in bed, watch for it and take advantage of it.
It's not just a one day job. Raspberry flowers come on every day for quite a long period, you'll need to spray each day as new flowers open.
I have used Compost tea successfully, never get any worms.

Did you notice any fruit flies around your raspberries?

larry gene; I'm unsure if I have any fruit flies, but I have noticed a few flies that looked like a regular fly but were about 1/4th the size and all black - wonder if they are fruit flies?

I don't know enough about all the insect identifications, but even though I think some of the wasp like things can be harmful I also read where they all pollinate - and then I read where others grew raspberries and never sprayed anything ever.

So I'd go over there and tend my row of raspberries and just watch all the activity, being somewhat jazzed about all the various pollinators doing their jobs.

Now I wonder if I shouldn't have gotten on a spray schedule of some kind.

I looked up raspberry beetle that you mentioned beeman but I can't honestly say I've seen one of them yet. (And I may have just overlooked it)

So I don't know what's making that almost too small to see thread thin little worm inside my berries but I for sure know I dropped the ball somewhere!!!

I think you have raspberry fruitworms. Google images for Byturus unicolor and see if they match. The best time to spray is just before blossoms open. Right now, you can rake back mulch so birds and other predators can get at the pupae waiting in the soil for next year.

On the very rare occasions when I want to spray anything that bees might come into contact with, including bt and spinosad, I cover the treated plants with row cover or tulle for two days to keep them out. Everybody's happy.

planatus; That is an awesome plan. I raked today (probably deeper than I should have - frustration...) I've got berries in all stages of development of course. I think I'm just going to pick and toss the ripe ones and see about what I can spray that will be safe to eat the remaining fruit as it develops provided I can get the right stuff to apply. Do you know what the days to harvest is for Spinosad? I want to find some pyrethrum too (or maybe Spinosad is that too?)

Anyway, thanks for the tips!!!

When I looked at a couple of extension pubs on this pest, they said no spray would be effective because of the position of the larvae. I would not spray anything right now. Next year when the insects are active again, something as mild as horticultural oil may do the trick. You're managing a pest that lays eggs on the outside of the blossom clusters, so that's the plant part that needs to be made inhospitable. Spinosad is a biological pesticide that might be indicated here during the narrow time window when the blossom clusters need protection. It's bad for bees, so covering treated plants for a few days would be in order.

planatus; Sounds good - I think I'll write off this years crop and chalk it up to experience. I did stop by the garden center in town and asked them, but they were not sure and she said she would call Iowa State University and get back to me.

I treat both the Caroline & Heritage as fall only, so I cut them down to the ground just before winter. The problem I have is most horticulture oil directions (if I recall) indicate to spray on branches/wood, etc. With my stuff being ground level, would you recommend I just spray the bed (ground) good with H/O prior to plant emergence? I'm thinking once they pop out of the ground next spring would be too late right?

Thanks!

I had the tiny worms in the fruit last September and suspect that they were brought north by tropical storms. I live in SW Mass. As soon as I knew that they were there, we stopped eating the berries. I cut down all of the canes and burned them. As I do not want to jeopardize any of the bee life, I will not spray the flowers. I will try brewing a mix of vinegar, garlic, cayenne and any other organic type nasty stuff that I can find, and spray before new growth starts. I believe that they may over-winter in the ground surrounding the plants

Hey everybody! Just happened to read these postings during my research on MY raspberry problem. I hope you have found (last year's) info on the "Spotted-wing Drosophila" at the Univ. of Rhode Island site. Very informative. I'm pretty convinced these are the little buggers destroying our berries (started last year). Hope someone has more info to add on possible treatment and/or eradication! ......Mark in N.Y.