Interesting. So you could at least salvage the fruit even if you think egg laying had already taken place.

Glad to see that this has been evaluated scientifically. It may mean that where there is a single generation of PC you could effectively control them with a single spray timed not more than 2 weeks after petal fall. Those synthetics- they save us from so much grueling work.

Interesting I could find only one whitetish worm under the crescent marking, similarly the Triazicide prevented laying or caused the eggs to fail.

I wonder if my homemade blackleaf 40 mix will work on the PC? Maybe i should mix it with some oil. Always wondered if nicotine would kill these buggers, they sure didn't kill my 86 year old grandma over the past 70 years :)

I think this is good news, but I'm not sure!

Is there any way to tell if the Imidan did the trick? I've been removing hundreds of plums with the PC scars on them, and these always seem to be the biggest ones on the tree. But then again, I'm a little leary about leaving a big fat plum with a big fat PC scar on it without knowing for sure if the little beast is dead or not.

Anyone have any input on this?

I feel the biggest fruit is often the earliest and smaller fruit may become just as large. I have more trouble with PC on plums but I've seen scarred fruit do fine. Nothing definitive.

Most times I find a scarred fruit I cut it open and see if there is a live bug in it or it is just cosmetic. After doing this thousands of times I have gotten pretty good at telling the serious scars from the non. I am still not perfect though. If it is light brown and an even "bowl" on the fruit its just a bite out of it. Darker brown and smaller size indicates a PC larva entry. For my plums this year there is so little PC damage that I just thinned anything with a scar, but the apples I kept some with hopefully bites only.

Scott

I was thinking about the question today as I examined plums and if you just cut a few open you'll know the ratio of cosmetic scarring to serious damage. If there is a tunnel deep into the fruit I doubt the fruit will make it.

Here are some pics of PC plums I picked up yesterday. After I took this photo, I cut them all open. All but one had tracks inside. Of course since these were drops one would expect a live curculio is what made them drop. Nothing but plums were hit.

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I think the lesson for me is to get rid of the brush pile. The only trees that were hit were near that brush pile.

Next year, I also plan to adjust my spraying regimen. This spring I sprayed a neonicotinoid at petal fall. The next spray was 12 days later after lots of rain in which I sprayed a pyrethroid, followed by 2 more pyrethroid sprays at 7 day intervals. The rain has been horrendous. Once it rained 3" between sprays, and once 2 1/2" b/t sprays.

Next year, based on the info by MSU, I plan to spray a neonicotinoid at petal fall, followed by a couple more covers of the same. It should be more rainfast, and offer some kickback.

The thing I find interesting is I hold off until last apples loose petals and on my own Euro plums that doesn't seem soon enough although I don't notice scarring until after I put down the Imidan.

At other sites I spray the same time plums may be clean or not, it varies from site to site, year to year. So if a different regimen works you can't be sure if its that or the year.

If I get a heavy set, it really doesn't matter because there are plenty of unscarred plums but it's a real problem if set is only moderate of less.

Is it possible that earlier scarring becomes more visible as plums enlarge?

I got considerably more PC strikes this year maybe 100 all together on just plums. So really there are just several PC beetles. The marked fruit gets easily thinned. I am careful that none make it to keep the pop. down for next season. I did read on the neonicotinoids and found they are very effective on Potato beetles. Some researchers are saying Honey bees are collapsing due to neonicotinoids. Bees losing their direction. IMO Bees are overworked/neglected then get hammered by parasites and residual chemicals.

My dad has 8 apple trees in his yard and has never done anything with them. I have been learning mostly from this site on how to take care of them. About 10 days or so ago I noticed something was making marks the apple on several of the trees. It ended up being PC so I purchased some Triazicide one and done at Wal-Mart, and sprayed the trees.

At the time one tree which has a lot of apples on was hit badly and I could not find an apple that did not have a mark on it. I checked them again yesterday and noticed the apples had grown noticeably and most had healed over and you could hardly notice the marks and I found a few that I could not even see a mark. There was a few that had marks that looked bad enough that I pulled the apple off. This was all done after I had thinned the fruit by hand.

So far this is the only spray I have used on them. I am still watching to see what else may turn up.

I've got apricots falling that have tracks inside them. Amazing how early PC was here. I've found several live ones in the yard. Really need to spray early and often if you want to beat these guys.