I had a plum tree for over a decade that would drop all its developing fruit each year. I only recognized the cause - PC ( with the crescent shaped cuts visible in every fruit ) after taking more of an interest in fruit trees. I managed to harvest a only a few fruits, by bagging, during the last year of its life; after harvest the tree began rapidly dying from some form of canker that was brewing hidden beneath its bark… and is now removed entirely. ( I did save two scions and successfully graft them onto two different trees below )
Now, two other plums are covered in fruit for the first time, and lo and behold, the vast majority of these new fruits have the crescent cuts also…
I would like a big fruit harvests and not to have to tediously bag a comparatively small quantity and hope they all mature. (5 out of 50 fully matured last attempt )
I do not want to spray the trees with something that will kill the bees, etc.
Ive read some sprays act as a rescue / curative for already infected fruit, but these seem to not be good for bees? Also, I cannot find the brand / what it is sold under except in seemingly large commercial high-priced quantities?
What can i do?
If there is a spray to use that actually works without killing the beneficial insects, what is the brand?
All the poison sprays kill everything pretty much… the curc is hard to kill so the big guns are needed. The only non-poison option I know of is Surround, that is what I use. It requires more sprays and more monitoring, but I lose almost none of my crop to PC (after thinning…) thanks to Surround. I probably get about 10% of fruits infected, but I can thin all of those out and still have a full crop. I always get a couple hot spots in my orchard where I have too many bites, this year I have one apricot that set a very light crop with heavy curc damage and I’m going to have to thin most of them. This is one tree out of over 100 so not too bad.
I sprayed my trees with Surround pretty often, about 4 times in two weeks, had to because of heavy rains. We had another early morning storm today, so I may have to spray again.
I spray about 15 trees and have to reload my sprayer once. Guess I should get a 2 gallon sprayer instead of the 1 gallon one.
I’ve had several hits on apples that I sprayed, don’t know the percentage because I can’t access all the fruit. Some trees worse than others. To my surprise my peaches look pretty clean compared to the apples and pears. Maybe because the spray covers that fruit better?
Juliet cherry has been sprayed as well, and haven’t hardly seen any hits.
How long does your PC season last @scottfsmith ? Do you get multiple generations or just one? Does Surround do well against OFM, coddling moth and apple maggots, or do you have to add insecticide? I have spinosad and permethrin if need be.
I will give surround a try, though I think this year is lost. Id like to try a neonicotnoid to save my fruit, but again I do not want to kill all of the beneficial insects - I also cant find a quantity without a large price-tag?
Do traps offer a significant help, or can 1 PC wreck an entire trees crop? Will traps utilizing plum essence with traps simply attract more PC into the area?
I have heard that Pyrethrin or pyrethrum (PyGanic, Pyrenone) is semi-effective when applied to apples at dusk on the first warm evening after petal fall, and I have used it that way. It doesn’t last. Instead, it is supposed to kill the curculios that are on the hoof, traveling into your orchard at that time, without major impact to the pollinators that are active during the day. This may or may not be sufficient for the level of your infestation because you have to get lucky to nuke them all on the same night. With apples, there is a cover spray treatment for codling moth, which typically follows the petal-fall spray shortly and which catches a few curculios, too.
Solution this year has been to do the first spray early (between petal fall and and chuck split) and reapply every ~10-14 days, sooner if it rains a lot. I’m spraying Triazicide + Immunox + NuFilm (sticker) at the maximum rate
So far I have very minimal strikes, planning on doing a total of 3-4 applications this year to see if that’s enough. Next year or the year after I’ll try to switch to Surround.
For me May is PC Month… I need to start spraying at the start of May and am wrapping things up by the first week of June. So all the spraying around rains is a big pain, but it is only one month of the year. There is a second generation but you don’t really notice it, not sure why.
Surround also makes a dent on the moth population, and I keep a low dose in my sprays throughout the season for that reason. I also include lots of other moth unfriendliness in my tank: spinosad, Madex, Grandevo, Venerate, codling moth granulosis, etc. Plus I use mating disruption (though taking a break this year to see how I do, they are expensive and hard to source). Not sure how Surround alone would work…
Scott,
I love to use non-toxic spray and has used Surround for at least 4-5 years. I did not do mating disruption and use other materials that you use. I have to say Surround alone did not work for me. I believe my timing of the spray was frequent and good. I only have 20+ trees.
Unfortunately, population of PC, OFM and other pests have been too much for Surround alone to handle. I wish everyone who use a non-toxic approach a success. I wished I had had a better result so I could keep doing it but I did not.
I’ve been doing @scottfsmith low-impact spray schedule for several years now and am really happy with the results. You definitely will still get damage from PC, but once you thin out the fruit with the crescent markings, you hopefully will have plenty of fruit left. My plan for apples is to thin out each cluster to two or three fruit, spray those clusters with Surround, and monitor. The next spray, remove any damaged fruit and spray again. As Scott says, some trees will be hit harder by the PC than others. For whatever reason, they don’t bother my peach tree, but love my Jonathan apple tree. If it rains, try and get another coat on ASAP, the PC don’t care about rainy nights like we do.
I was out spraying last night and for the first time caught a PC in action. Squished her good.
Same here, I have 4 peach trees, two each in areas about 200 feet from the others. I would’ve expected to see a lot of damaged peach fruitlets by now, ie oozing gel coming out of them due to PC hits, but I’ve seen little evidence of this. Maybe it’s because the clay adheres to the fuzzy fruitlets better?
I’ve had quite a few hits on my apples despite hitting them with 4 sprays of Surround in two weeks. They seem to hit my Roxbury Russet tree the most, Macoun the least. Hard to get effective coverage when it rains so much.
Of course, my biggest pest to worry about is squirrels, it would appear they haven’t discovered my fruitlets quite yet, but I’m just waiting for the other shoe to drop…
I always hypothesized that the fuzz on the peach was the reason they are not attacked by PC. I can completely coat the baby peaches with the slurry of Surround and other stuff whereas the slurry forms beads and runs off the apples.
Now that I think about it, I can’t recall ever seeing a PC mark on a peach.
“If there is a spray to use that actually works without killing the beneficial insects, what is the brand?”
If you do not want to kill bees then spray when the bees are not on the trees. Growers have been doing it for years. This is after petal fall.
There is no insecticide available to the home grower that does not kill beneficial insects that happen to be on the tree when sprayed. The lesser evil of insecticides is permethrin, simply because it is the only effective options to kill plum curculio for the home grower (or the synthetic versions of permethrin).
Your only other option is surround or bagging which protect the fruit instead of killing insects as others have mentioned…
Your PCare very mild-mannered. Wish mine behaved like yours.
No PC on peaches?!!! That would be heaven for me. I wish I took pics of how many PC each of my peaches got from PC (in addition to OFM) while the fruit still had Surround on.
I am happy for you. To be honest, I am very envious!!
One issue with PC on peaches is the bites are often not noticeable due to the fuzz. Some years I have thought my peaches were not getting any bites at all, and then in a few weeks a lot of fruit is dropping. PC bites often don’t ooze, only the OFM is reliably oozing. If you rub off the fuzz at the tip you can see the bite; any slight deformation there is a sign to look for a PC bite under the fuzz.
I probably need to hit my peaches in fact, they have only a minimal coating on them as currently it is apples and plums that the PC is liking the most. The PC in my orchard starts out preferring apricots (there is nothing else large), then asian pears, then apples and plums, and finally E plums. Peaches are never at the top of their list but they will definitely go after them (cherries are even further down, also not on their list but if I don’t put Surround on them at all they will get nailed). In my spraying I focus on what they are currently targeting the most, so pears didn’t get a big hit in my last spray as they are in a breather period there, and I mainly focused on apples and plums. Also apricots they stay interested in so am hitting them heavily as well. They don’t ever really lose interest in apricots and I get some of my largest % damage on them. This year I had a light set as well so will be getting less than full crops.
I posted these into a separate thread the other day but since most activity is here it seems fitting to place them here. PC on my peach and nectarines in south eastern NJ.
They are a fan of every tree that I am growing. Surround did a good job keeping them at bay last year but this year seems to be another story. Maybe its something I did or maybe the weather. My first year getting hit with fire blight on my apples too. Rough season and we are just beginning.
I have acquired, and am now using, Surround. I am attempting to target the fruits specifically, rather than canopy, to avoid an entirely white-coated tree. I find that it does not adhere to some plums very well. To date, I have only seen PC activity on the plums, despite apple and peach in proximity. Hopefully this does not change.
Does a good coating of kaolin clay also help prevent birds from targeting the fruits?
