Belay, Bifentrin, Danitol, Imidan, Lannate, Delegate, Diazinon, Venom, Verdepryn, Altacor. (Some of these are restricted use - I recommend any serious fruit grower get a private license from your state - it is not that hard to get and it is great to have.) When used in proper sequence it is unusual to see too much damage to Asian or Olympic pears, but admittedly, BMSBs are hard to control unless you attack with Lannate or an equivalent but then you have to watch your PHI. Also, avoid pyrethoids post bloom because they zap enemies of the stink bugs if the stink bugs are an issue.
The only damage I had on my GS apples this year was from BMSBs. Pears were OK. But, I recommend you consult with your county agent to make sure you are identifying the correct pest. I am lucky because all I have to do is consult with Dr. Chris Berg at the Alison Smith AREC in Winchester, but most states have an equivalent. One thing I have learned is that Samurai wasps do a job on stink bugs without unintended consequences - maybe you can get a controlled release from your land grant folks. The scientists are very enthusiastic about these wasps.
I have a spray license but I donāt like having to spray insecticide more than 3 times a season and I sure want to know what Iām targeting. That is what Iām trying to find out here.
You donāt need a spray license to get the materials needed to protect fruit, there is usually an unrestricted material that will be adequate to protect fruit, and that is where this forum comes in handy.
I had hoped that my problem was common enough that I would get an answer by posting of it on this forum- this works as well for me as shipping samples to a Cornell pathologist or entomologist. I plan to take some photos today and send them to Cornell, but I doubt I will get any definitive answers.
Typical Spray Bulletin for Commercial Growers anticipates 11 or more sprays from applying Dormant oil and Cuprofix (March) until 8th cover spray (Includes fungicides, fireblight control, etc.). Key is integrated pest management and very carefully reading the Bulletin and consulting with the Cornell Maryblyt. Some restricted pesticides are about the only thing that works for early season mite control and yes BMSBs, until we can get the Samurai wasp (or other effective predator) population established, which, BTW, is also rough on the Spotted Lantern Fly or so the geeks say.
I have been managing home orchards as my full time job for 30 years now (it has been part of it for over half a century, starting with the orchard I planted for my father in about '69). Cornell only researches and reliably instructs commercial fruit production and if I followed their recommendations I would have failed to succeed in my business, which now includes over 100 orchards in my region. It is my low spray approach that often means only 2 synthetic sprays for the entire season to obtain sound, if not pristine fruit, that helped me successfully grow my business. A small but growing number of customers are now opting for a 4-spray non-toxic approach using Surround as the main protectant.
The key is to study your own pests and take some risks to find out the point of least intervention with best results that suits you or the customer.
Even my customers that want pristine fruit are provided that with significantly less spray input than suggested by Cornell guidelines, because pest pressure in small orchards is significantly less than in the many acres of monoculture required of commercial production. I have never seen anything out of Cornell that suggests this, which is just one example of their lack of focus on non-commercial production. Have you ever seen a speck of research on the relationship between the size of an orchard and the speed of development of resistance to pesticides? Thatās another example.
If Cornell had any mandate to research and teach about home orcharding, this forum would not be so useful. The skilled orchard keeper uses guidelines as suggestions, not as iron-clad, essential recipes. After about 10 years of managing them I began to get the feel of it, but I will never be a master, with or without Cornellās help, but if I sprayed as much as they suggest, my business would likely have failed.
You guys in upper NY are lucky and I agree less sprays probably work well there. But, here the middle of the Shenandoah Valley, we have nearly every bug, fungus, and bacteria known. Plus, we have high temps and high moisture so I have no doubt your spray bulletin should be different from yours. For instance, our Ginger Golds were ripe in the beginning of August, even late July and our Honeycrisps around August 20th. I would love to convert to a more organic operation with fewer pesticides, but with only my Limbertwigs yet to be picked (and they have damage from Plum Curculio here and there) it is hard.
Interestingly, the fruit scientists here are adamant that commercial organic orchards will not work well in Virginia, WVA, etc. The issues I mentioned above preclude it they say. However, I am a bit more optimistic. Resistant root stocks (many developed at Cornell) are changing the game. If I could spray as infrequently as even 6-7 times per year I would be ecstatic. But, one pomonologist (sp??), Dr. Sherif, is working on developing a Virginia apple that will do well here - combination of Honeycrisp and Cameo I believe.
It was great to hear your point of view and perhaps it can be my hope for a less expensive and simpler future.
I fear your weather and pests are becoming ours and that 2-spray ideal is being challenged more every year. Marsoninna leaf blotch, in particular, is becoming a huge impediment to a low-spray program and 5 years ago it wasnāt even on the radar.
It automatically is requiring 2 more fungicide sprays in summer at many sites I manage, or trees donāt hold onto leaves long enough to produce really good fruit, especially for later varieties.
If your site was higher up, it would be easier, I bet. Years ago I went to a site outside Charlottesville, VA as part of a NAFEX tour. His orchard was high up in the hills and he grew old strain yellow delicious without spray and sold organic sweet cider he made from them. Of course, it wasnāt the source of the lionās share of his income.
I dropped off pears to my cooperative extension yesterday. My current theory is that rain and warm nights caused water to transfer rot once the skins of fruit were penetrated. Iām not satisfied with that but itās all Iāve got. Letās see what Cornell comes up with. I will probably have to mail fruit directly to the university to get a final response (if not answer).
Our elevation is 1100 NVGD. Normally the Valley is considered semi-arid - hence its huge production of corn, beans, milo, barley, and wheat. But in 2018 we had 84ā of rain and starting in late Aug of this year until now 20+ inches. Go figure. In another irony the Valley is now considered a corn deficit area because we have so manny chickens, turkeys, and cows. There are even turkey pedestals on old US 11 south of New Market and and north of Bridgewater celebrating the turkey as the savior of the area - we have huge turkey and chicken plants in Rockingham County. We do have an excellent fruit and vegetable auction site in Dayton and several heritage orchards. But, controlling the pests is a challenge. Sorry to hear bad things are migrating north, but that has been predicted with climate change. Also causes strain on beef and dairy cattle.
A ;warming and shrinking planet where pests travel with exported goods and even traveling people is a challenging combination- even as the speed of technological advancement increases exponentially, which is a part of the same animal. Nature seems to despise a monopoly- which would be us.
Iām wondering if your pest could be Spotted Wing Drosophila. I see similar rot associated with their egg laying on figs. Supposedly they donāt target pome crops, but this says they do go for Asian Pears. https://hort.extension.wisc.edu/articles/spotted-wing-drosophila/
I had the same problem this year. I donāt think Iāve had it before, but this was also the first year that I completely netted the tree (fine-mesh, white translucent), so that could also have had an impact. Of course, part of it could just be that I got a lot more fruit than I have in the past, making it more likely that I noticed this issue- itās harder to see a trend when you only get a handful of fruit (if that much) vs 35-40lbs.
Only a portion of the fruit had the internal browning/rot. Mild cases impacted texture, but didnāt completely destroy the fruit (my wife was brave enough to eat it anywaysā¦), while I would generally just cut around it.
While I did let the fruit hang into November, I donāt think it was from hanging too long, as I saw some of the internal browning in early October, before Korean Giant is generally fully ripe. It is possible that over-cropping may have some part to play, as my tree was heavily laden.
Iām a fan of your stink bug theory regarding late season KG Asian pear rot. Noticed high concentrations in my area around the same time as pears were rotting. The above rot Bob is showing I believe is an issue not related to the stink bugs. My thought is that @BobVance issue is caused from a condition I sometimes see when i have to many pears on a tree. Sometimes flavor is bad or nutrients are low if a pear is carrying to much fruit. The fruit is never 100% in that situation. In my situation it happens when there is a glut of water, to much foliage, cold year where there is not enough heat to concentrate sugars (eg.tree is shaded). In my area itās very rare. The rot im referring to with Korean Giant regarding stink bugs is started external not internal break down like Bob shows here. They are two seperate rot issues. The internal rot Bob describes I call that internal break down and some pears normally high in sugar are more prone to it than others Clapps favorite pear . Of course fungus or bacteria can speed a natural process a long
There was definitely too much fruit. I was actually pretty surprised that it sized up so well. I measured one at 1.5 pounds and there were quite a few in the 1-1.3 pound range.
Brix wasnāt as high as in past years, but was still pretty good to eat. In the past, Iāve often had 18 brix from Korean Giant (highest brix Asian pear for me). This time, it was generally around 14, which is similar to many other Asian pears here (some are even lower (11-12) and I am not fond of the low-brix options).
Netting probably added a bit of shading, but I bet it will work a lot better if I thin more and/or we get less of a cloudy and wet year.
That makes perfect sense as you describe it. Korean giant has been more prone to rot in my experience but it may be its higher sugar content. The stink bugs love it but maybe they are like us and prefer a good tasting pear. Perhaps the internal rot is related to the heavier crop. We will know more soon.
I think that harvesting later makes them vulnerable to internal browning. Iāve observed this in Korean Giant, Drippin Honey, and Shin Li when picked super ripe. They are all fine when I pick them but develop that core breakdown when stored in the fridge. I find that some Asian pears can still hang pretty well for a duration even after theyāve ripened, but their quality doesnāt change much for the better, and they end up perhaps losing some crunch and crispness.
Some of mine ripened much earlier this year beginning in the 2nd half of September. Our summer was very hot, which may have contributed to this. I normally donāt pick them until the first week of October. They ripened one by one over a 3-4 week duration.
I left a few Korean giant Asian pears on the tree to hang for a long while and finally the wind knocked one of them down. It was huge and pretty nice looking Asian pear.
Picked first Korean Giant today. Seeds were very black. No internal rot.
Picked Drippen Honey Sept 9th and there was small amount of internal rot. Stored some in refrigerator for 18 days and rot was much worse. Perhaps I should have picked them sooner before the rot started. https://postharvest.ucdavis.edu/disorders/asian-pear-internal-browning
Plus, we have high temps and high moisture so I have no doubt your spray bulletin should be different from yours. For instance, our Ginger Golds were ripe in the beginning of August, even late July and our Honeycrisps around August 20th. I would love to convert to a more organic operation with fewer pesticides, but with only my Limbertwigs yet to be picked (and they have damage from Plum Curculio here and there) it is hard.
