Sevin; not seven, not sevan
I thought it looked funny, but it passed my spell-check.
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So instead of 3 tablespoons per gallon do maybe 4.
No official comment. The label is the law, albeit unenforceable in this case.
Belay looks much safer for bees than Actara, judging from their respective labels.
I sprayed Avaunt on my apples and Actara on peaches and plums at petal fall and 10 days later with no sign of PC damage. Here in the south the sprays need to continue for several months. I have been rotating Ortho (Assail), Delegate and Triazicide on everything for the last month and can report very little bug damage other than bird pecking. Not sure what the take away is except I have pretty clean fruit and my pocket book is lighter from $ spent on those sprays.
I agree. We need to rely on our own experiences because the data published by the âexpertsâ is a lot more inconsistent than I would expect. I took a few minutes and compared the insecticide efficacy charts for some key insects from three university sources - the Penn State link I posted, the Southeast Peach Management guide you posted and the Southeast Apple Management guide I often use. In some cases the efficacy numbers often do not agree by substantial amounts. Even the effectiveness pulled from the apple and peach publications for the southeast which use many of same entomologist do not agree a much as I would expect.
Iâm surprised that the âexpertsâ donât agree more on which chemical kills which bug.
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Alan,
I think many of the pyrethroids do a good job controlling pc and stink bug, but just not top notch control like actara belay and phosmet . Iâve used actara for a few years and used a little belay this year. I always get a few pc scars but it seems to kill the larva inside on stone fruit. I think youâve reported phosmet does the same, so there is some rescue with these. I donât think pyrethroids have any rescue activity, but they are very good contact sprays.
The pecan orchard of my wifeâs uncle uses Proaxis, the same a.i. in triazicide and gets very good control the very similar snout beetle which affects pecans. However that product is oil based. I donât know if that would make a difference.
I think belay is pretty lethal to bees. I once checked the ld50 for it and as I recall it was about the same as actara .
Iâm on my phone right now waiting for a water tank to fill, so I canât Google it.
Thanks for posting this thread Alan. Good to hear these experiences.
That could be because insects regularly build up resistance to pesticides. The resistant strains can develop at different times and degrees in different areas. Sometimes the dosage to kill a pest can increase by a hundred fold or more in just a few yrs. How much that factors into home owners results is a big question mark.
The extension agents and pesticide consultants have a difficult job. Anyone posting here how thinks they have a better handle on these things than the pros may be over rating their experience.
I used it on some euro plums at petal fall, but only have about a dozen plums total on the trees. They all seem okay. I used it on a Liberty, Honeycrisp, and Gala apple and have no bites. I have a crabapple with different varieties grafted onto it that I didnât spray. Any apple on that tree, including the crabs, seems to be hit badly. Used it on a Veteran peach with a few dozen peaches and they seem okay, but Iâm not sure they get hit anyway.
I beg to differ. From my 25 years of experience I can say with absolute confidence that guidelines for commercial fruit production are not nearly as useful as information I get from growers right on this forum and from my own experience. Iâm telling you FN, growing a few fruit trees surrounded by other species- sometimes for miles and miles, is very different than managing a commercial orchard of typical size. The information from extension agents comes purely from research on commercial production.
If you mean that our information is less accurate for home production than theirs for commercial production, I can buy that, but they donât know crapola about home orcharding.
However, I think you make an excellent point about developed resistance, but the tests of efficacy are supposed to be on pests that have not yet developed resistance, I believe.
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Thatâs likely true. Iâve never had issues killing any fruit pest. However when trying to kill corn ear worms, aka cotton boll worms, the resistance built up in cotton carries over to everything else.
You probably arenât facing resistance issues in your orchards. Certainly not to the degree that commercial orchardists do.
No the tests of pesticide efficacy will be on the pests as they exist in the orchard situation. Thatâs what counts. So what if it kills a non resistant pest when there arenât any of those left. The degree of pesticide resistance can vary widely across large commercial districts so results can and will vary.
I just think itâs disrespectful to knock the professional pest agents and consultants. Lots of people think after a search on WebMD that they know more than their doctors. In truth they donât have a clue.
Excellent point. I understand that Imidan is no longer effective against certain insects in certain areas due to its high use over many years. It may not make sense for me to compare the Penn State efficacy chart to the similar chart for the southeast US.
When just considering the data for the southeast US, I noticed that Imidan is rated as a 3 or moderate for OFM on peaches, but a 5 or high for the same insect on Apples. I would expect some deviation for the effectiveness of a given insecticide against a given insect from crop to crop, but I see more deviation than I expect between apples and peaches and also from region to region even considering the resistance factor.
I also noticed that in several research trials in my state, the control block with no treatment experienced less insect damage than the blocks that received treatment from several different products. This type of academic research is really confusing to a average grower like myself.
It would be great if I had a PHD in entomology but I donât. I just need to spray the right material against the bugs at the right time. Following the advice from the âexpertsâ in my two acres of tree fruit has not worked as well as expected. Using trial and error, I will eventually solve the problem, but Iâm going to loose a lot of valuable fruit in the meantime.
But were the differences statistically significant? Most of the time that just says the pesticide had no control. Measure the same thing twice and you get a bit different answer. Or itâs even possible in a few cases that the pesticide killed the beneficials and thereby reduced control of the pest.
It was a replicated trial and the study indicated the difference was statistically significant, which is why I was so confused. Not sure if they tested it again the following year.
This stuff should not be so difficult! I just want to kill the bugs that destroy my fruit in a safe and approved manor.
One very experienced local grower has developed a solution. Imidan, Imidan, Imidan, Imidan, Venum, Imidan, Imidan, Imidan. His apples looked perfect.
Thatâs possibly just a fluke. But could be like the effect of Sevin on spider mites. Sevin kills the beneficials and the mites explode.
Just to add to the confusion, I note that while the label on permethrin [Eight] warns against using the product on apples after petal fall to avoid harming predatory mites, the label on Sevin makes no such warning
In my experience, when Cornell gives information about the relative effectiveness of pesticides against any given pest, they include only data about the efficacy on non-resistant strains and sometimes advise that resistance may make the information irrelevant in orchards that have resistant strains.
Maybe other universities do it differently, but if they do, they should explain the nature of the data because resistance is variable from orchard to orchardâŚ
I wonder if one is harder on beneficial predatory mites than the other. Iâve had problems with both classes of pesticide, but with Asana, a pyrethroid, Iâve gotten other things, like cottony scale on peaches and whitefly in apples- and I mean serious whitefly that weakened the trees if left untreated. Of course, thereâs no way of knowing if it was the pyrethroid, but these types of trouble started cropping up as soon as we made the switch from Imidan.
That really doesnât make sense and isnât useful when resistance is an issue. How do they know the specimen in question is non resistant? Only way I know is to see how easy it is to kill with a particular pesticide.
Youâve got to work with the pests as they are in orchards at the current time. So results can vary across locations depending on how much resistance has built up
At some point there wonât be any non resistant strains left. What does Cornell do then, throw up there hands and quit testing? No theyâre going to test on what theyâve got.