A study by Cornell indicates that fungicides, generally believed to be harmless, may have a role in bee decline.
See below
Mike
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The study links petroleum-based human-designed fungicides with the amplification of some insectides, thus harming bumblebee populations in the study area.
I find this article misleading and the presentation of the data/information unprofessional. What fungicides did they test? Did all fungicides have the same result or only chlorothalonil? The article implies more than chlorothalonil but nothing else mentioned by name. What insecticides increased toxicity to bees when combined with fungicides - article implies all insecticides? At least for fruit you should not be spraying insecticide and fungicides together when the tree is in bloom - so does this really apply to fruit trees? Commercial growers spray insecticides that harmful to bees after petal fall …
I am sure the study is academic - the article is not.
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Article title and photo are misleading because the research was about Bumblebees, not honey bees.
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The thing you have to understand about such studies and articles that follow is that the researchers are trying to puzzle together clues, publishers are trying to put together interesting content. While the researchers may not be premature in drawing conclusions, coverage of research is generally less restrained. The general public ends up constantly being over-alarmed by preliminary studies. This is even more prevalent in the realm of medical and diet research and in the end, probably makes the public excessively skeptical about scientific research in general, or at least, grossly misinformed about what the research proves.
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Large commercial growers have huge truck sprayers and when it’s time to put on sprays it’s time. They do the best they can to make sure things are not in bloom when they can. I have had half a dozen bee keepers tell me their bees were sprayed while working flowers. It’s not all about fruit growers because soybeans, alfalfa etc. need sprays http://entomology.k-state.edu/extension/insect-information/crop-pests/alfalfa/alfalfa-weevil.html. Homeowners spray yards for white Dutch clovers as do farmers, horse ranchers etc. https://www.chronofhorse.com/forum/forum/discussion-forums/around-the-farm/105263-help-massive-weed-issues-in-hay-field-what-can-i-do-update. The public is spraying white Dutch clover in bloom in their yards and fields. Zika carrying mosquito sprays are a problem https://www.google.com/amp/s/amp.cnn.com/cnn/2016/09/01/health/zika-spraying-honeybees/index.html. They get sprayed frequently during almond bloom http://thealmonddoctor.com/2017/01/24/protecting-honey-bees-bloom/. Not everything blooms at the same time so people such as me grow a peach an apple and a pear in one row so disease cannot tip through the orchard. The problem is though that’s effective one thing is blooming while another is at petal fall.
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I believe the significance of the report is that it points to fungicides damaging bees.
Bee damage from insecticides during bloom is well known, but damage from fungicides is something else to think about.
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It’s been known for quite some time that fungicides can have detrimental effects on bees particularly when it comes to synergistic effects with insecticides. In that sense the article is a bit fallacious in that it’s not “new”, “surprising”, or “shocking”, as the article states. Not in any way attacking your post Mike, just pointing out a misconception in the article.
I’ve even seen a ranking of the relative bee safety of several fungicides. This has been known at least since 2009, probably earlier.
https://naldc.nal.usda.gov/download/30692/PDF
I don’t get over excited about these stories because bees face a host of natural and artificial challenges, so it’s about perspective, imo.
I’ve been spraying fruit trees with insecticides/fungicides for over a decade at my house, and had a neighbor who kept bees near me for years. He finally quit and moved to an assisted living facility due to age.
Similarly, I spray some very bee lethal stuff at the farm orchard and see tons of bees every year. The last two years I’ve had a friend put up a bee capture box at the orchard and he’s caught swarms both years.
One just has to be careful. Don’t spray during bloom, minimize blooming weeds, etc. I kill blooming clover with Stinger in the aisle ways. I have used a weed eater to cut down blooming yellow rocket under the trees before spraying.
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No apology needed as I don’t claim any allegiance to the article.
It is just something I ran across and thought that it might be of interest here. The linking of the article was not meant as a “the sky is falling” or an “I told ya so” shout-out.
However I do think that we might be seeing an autonomic response here.
The title did say “… emerge as a possible villain”.
The first “man-made” chemical ever created was created the first time “man” started a fire. As we learn more we can become more judicious in our use of these but anyone who thinks that these can or will or should be eliminated has a loooooong wait.
@alan 's point is also well made.
At this time we have to do the best we can to manage the risk in exchange for the benefit.
Mike
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It says nothing about all fungicides damaging all bees.
It points to a specific chemical category of fungicide amplifying certain insectides.
Yes, the study itself is sound and re-affirms my dislike for organo-phosphate pesticides.
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I looked at the study, they didn’t get a super strong correlation and they checked for enough different things that you start running into the possibility that one of them will work by sheer random probability. The authors themselves acknowledge that in the following statement toward the end of the paper
While suggestive, we caution against over-interpretation of correlational patterns between pathogens and bee declines that may not be indicative of larger patterns or causal mechanisms.
In other words, things still remain clear as mud on this issue.
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I did some more research and I was surprised to find that multiple classes of fungicides are moderately or highly toxic to bees.
I’m not familiar with all of the fungicides on the list but Captan caught my attention
Captan is the foundation for almost all conventional spray programs for apples, either sprayed alone or in a mix with other fungicides to reduce the chance of resistance to single mode of action fungicides.
The list of fungicides in in table 2 of the attached link:
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I’m sure you are correct – esp. if referring to mode of action. But it is far from being true of all fungicides. It is even less true when application directions and dosage are followed.
Richard
I was happy to see that Streptomycin was very low toxicity since that is the only fungicide that I spray during bloom.
Also noticed the name of quite a few fungicides that have been discussed on Growing Fruit are also low toxicity.
Just 2 fungicides listed as high toxicity that I’m not familiar with
Here’s your original statement:
If you had instead stated:
it points to some fungicides damaging bubblebees
… we’d be in full agreement. 
Further this reference:
refers to risk to bees, not toxicity as you stated:
Isn’t streptomycin an anti-bacterial not a fungicide?
It is listed at the bottom of page 14 (see link above) as an antibiotic fungicide with mode of action 25.
Here is the specimen label from CDMS: http://www.cdms.net/ldat/ld315001.pdf
The “Directions For Use” on page 2 contains important application instructions.
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I would say mostly yes. I’m not a toxicologist, but its my understanding that antibiodics target bacteria, but the label calls it a fungicide/bactericide Most spray manuals group it and other antibiotics like oxytetracycline with “fungicides”
Copper is another material that is normally grouped with fungicides that is not technically not a fungicide in my opinion
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