My experience looking inside apples is 99% of the time the PC will be crushed, but on rare occasions when the fruit is not growing fast enough they can come to maturity. I have found mature worms in crabapples and apples that naturally aborted.
For stone fruits, I think the worm needs to be reasonably large when the fruit drops (say 1/4" long) for it to be able to eat enough of the rest of the fruit on the ground to mature and dig out before the fruit rots. You need to pick them up something like a week within drop or you may find some fruits with a small round hole in the outside and no worm inside - the worm got away. I check many fruits I pick up for this exit hole to see if I am not too late on picking the drops. Note that if you see what looks like an exit hole but there is still a worm in the fruit then you probably have an OFM not a curculioā¦ do the hand crawl test to verify. It could also have been that there were multiple curcs in the same fruit.
I am losing a very large % of my apricots this year to PC, Iām not sure what happened as I sprayed them well. My guess is we had several periods of heavy rains followed by warm nights where I could not get the Surround back on. The good news is the PC seemed to mainly hang out there all spring, I have much less damage than usual on everything else.
Noticing almost no āJune Dropā here this year so far (usually happens here in May) possibly because all apples were PC bite-free at bagging plus picked up the tip here to bag the King apple with stoutest stem. Last year 1/3 of my bags dropped.
Scott, are you talking about holes look like this? These are my Santa Rosa plum that I found Turing reddish. I know they sooner or later will drop. I cut all 5 open and only found two PC worms so the other three possible got away already?
OK here is an apricot with an exit hole, the small dark hole right in the center goes all the way through the wall. After taking the picture I popped it open and you can see it had several more worms still inside. The curc was very busy on my cots this spring!
Amazing the difference in your pressure there. PC doesnāt seem to be active when apricots first form their fruit but I used to spray them at the same time as the rest of my trees. This year I gave them no insecticide and they are fine. Should have gotten some Indar on sooner to avoid scab is all.
@scottfsmith I have purchased Steinernema riobrave from Southeastern Insectaries, and the Fedex truck dropped them off embedded in a slightly dripping ziplock baggie with sodium polyacrylate gel (i.e. the little crystals in baby diapers). The little buggers are super cute and viable. I uploaded a quick video I took of them swimming around to https://youtu.be/z8aAKo5X7XI . Their density is very high, as is viability.
I am going to administer them around my fruit trees and report on their efficacy later.
I have found 30-50 sweet cherries will good size larvae inside of them. PC really did a number. Must have been because the cherries sized up faster then everything else. I got rid of i think all the bad ones///really easy to spot because the infested ones donāt change colorāthey stay more yellow and they start to darken and when you squeeze them they are hollow. In the past the sweet cherry didnāt get hit that hard. My june drop on one apple tree has lot of fruits with hits, but iāve yet to find a larvae in one.
Its a never ending battle but its been going on for over a decade. If i get the sprays on the damage is minimalāits just getting those windows of weather to do it (dry/calm) Sweet cherries here are a huge gamble so a lot of years if pc gets a lot, oh well. Any rain right now and everything would rot. I might be able to squeeze them thru because it looks very dry the next week. I have to wrap the tree with netting though because the birds are feasting.
Sprayed imidan may 14 and may 24 with sticker. Checked today could not find any PC damage. Hoping to avoid insecticides for rest of year but will need fungicide for brown rot.
Sprayed Carbaryl (Sevin) on the apples and pears 2 days ago. I saw very little PC damage but a lot of coddling moth strikes (ugh). There is no way that I could have sprayed during those 90 degree days.
Iām in south eastern NJ and finally had some luck in my fight against these tiny menaces with a few coats of surround. I try to avoid using anything toxic if i can avoid it but it has been a struggle. Having trees that look like ghosts is a bit weird though.
That paper highlights one of the reasons why temperature is so highly correlated with damage. The curcās engine is running 10x faster when it is warm.
@IL847 ,
I will try using a trunk wrap smeared with TangleFoot earlier in the spring. I want to see if I could caught any PC that will ā walkā up the trunk during cool early spring time.
The trial used day time temp with 68 F (20 C) be the temp that a majority of PC will fly. Still, we canāt underestimate temp lower than 68 as some PC will be ready to fly.
The time has come. I bought some tarps today to cover the ribes I have growing under the plums. Rain from is expected off and on till 2pm. Thursday take the war to them.
