Dick
I tried to make it clear that I couldn't back up what I was saying with any research
It's just my understanding from what I've read
I'm trying to find where I got that information
Dave
Dick
I tried to make it clear that I couldn't back up what I was saying with any research
It's just my understanding from what I've read
I'm trying to find where I got that information
Dave
A recent study done at UC Davis indicates the mode of action of Oxalic Acid is through contact. In part:
"A final study to determine how the
acid appears to kill mites was conducted
using an elaborate system of modified hive
components that allowed only vapor, food
sharing or individual contact between
treated and non-treated mite infested bees.
It appears as though the mode of action of
the oxalic acid solution is by direct body
contact."
For the whole article see:
http://www.beesource.com/cgi-bin/ubb...290;p=1#000003
George-
Dulcius ex asperis
ok
I guess I got that information here
www.mitegone.com/forms/Manual.pdf
obviously an ad not research
also for formic not oxalic
but that's where I got the impression for the method that organic acids use to harm the mites
can anybody find any more specific info??
Dave
>>hit by a hammer
I like it!!
Axtmann, please allow me to pick your brain,..
How many treatments do you normally apply after your honey flow? ie, fall application.
When is your honeyflow?
When is your regular OA treatment schedule?
How long does a yard treatment, lets say 30 hives, take start to finish prep and all?
What is your thoughts on its effectiveness of mite drop? Do you see 80% as everyone is saying?
Why is the above freezing temp important?
Or is it just a easy mark point for colony cluster?
Or does the compactiveness of the cluster B/W 5 degrees and freezing significant for vapour penetration?
Sorry for all the questions, I am told you are most experienced with this method.
Ian Steppler >> Canadian Beekeeper
www.stepplerfarms.com
Thanks Dave & George. I was just curious There is some "stuff" out there to be googled that mentions systemic action and there is some "stuff" out there to be googled that mentions contact as mode of action. More important, I guess, is that it works.
I have a commercial pesticide applicator's license, so I have a pretty good understanding of how various chemicals work on arthropods. I'll admit that some chemicals seem to fit both categories, contact and systemic. Here are the differences as I interpret them:
Contact chemicals kill on contact. These compounds are only effective for a short period of time, usually "on contact." They break down or bind with other compounds in the environment fairly quickly and lose their intended effectiveness. (I do know that some of the by-products of chemical breaking down are toxic as well, and these can harm organisms as well.)
Systemic chemicals are absorbed into the host or remain on the host for an extended period of time and usually work on the target organisms feed on the host.
So, if the OA is absorbed into the honey, wax, or bees, it could be considered a systemic pesticide. If it remains more volatile, it's likely a contact pesticide. The way I would judge OA lies in how quickly mites are killed and the length of time the treatment continues to kill mites. I haven't used OA personally, so
1) Do mites begin dropping very quickly after the treatment? If they do, it's probably a contact toxin.
2) Does the OA take a period of time before it begins working, such as a day or more? If it does, it's likely a systemic poison.
3) Does OA residue continue to kill mites, preventing growth of the mite population, for an extended period after application? If mites continue to die for weeks after application, it's almost certainly systemic.
Like Dick Allen said, the important thing is that it works.
Ian
Axtmann, please allow me to pick your brain,..
...How many treatments do you normally apply after your honey flow? ie, fall application....
This year I started August 10th and made 3 treatments a week apart on my old (last year) colonies. My splits/swarm during summer without brood had already 1 treatment when they have the first eggs. They received one more in November.
My colonies had no treatment in spring thatÂ’s why I start right after honey flow ends. A second reason is; each mite I kill in August canÂ’t make any damage on my winter bees.
I vaporized the hives one more in November and the drop was between approx 180 and 280 mites in 3 weeks. Last treatment was on December 6th and so far most colonies had less than 10 mites till now.
IMO maybe the last treatment was not necessary.
I have friends they have similar good results without treating them 3-4 times after honey flow. They treat in spring and two times (week or two apart) as soon as there are no brood in the hives.
....When is your honeyflow?...
This year honey flow ends end of July.
...When is your regular OA treatment schedule?...
As soon as I take the honey supers off, I feed syrup (3kg ea hive) and 3 day later I start with OA. This works for me for the last 5 years.
...How long does a yard treatment, lets say 30 hives, take start to finish prep and all?...
I have two - JB200 electric vaporizer and can treat 10 hives in about 15 minutes. With four I could treat 20 hives the same time and would be finish in 40 minutes. But time is not so important for me.
I let the vaporizers heat for 80 second before I switch off and wait 10 more second before I remove them and go to the next hives.
...What is your thoughts on its effectiveness of mite drop? Do you see 80% as everyone is saying?...
IMO if I treat a swarm on empty frames with starter strips there are no mite left. I would say I kill more than 90% of all mites in my colonies. There is an expression nothing is 100%.
If I treat and there is some brood left the mite problem slowly starts again. Bigger problems are careless neighbourhood beekeeper.
Perizin (chumafos liquid) from Bayer has a kill rate up to 85%. Some beekeeper here treating with Perizin (single winter treatment) and formic on a cleaning rag, or a Nassenheider, right after the honey supers are off. I gave up, I have better results with OA, itÂ’s easier to handle and saver for both.. bees and myself.
...Why is the above freezing temp important?
Or is it just a easy mark point for colony cluster?
Or does the compactiveness of the cluster B/W 5 degrees and freezing significant for vapour penetration?...
The vaporizer produce heat and bees starts fanning and moving. Above freezing the cluster are loose and bees can find there way back to the cluster. I treat only when I can see some bees moving.
During evaporation OA fog covers the cluster and as soon bees move inside to warm up they bring the acid to the other bees. After a treatment I can see lots of white bees. They are not wet; there hairs are covert with microscopic fine OA crystals.
Jon Kieckhefer
After evaporation it takes a few day before mites start dropping. OA is not an instant killer.
http://www.mellifera.de/engl2.htm
In earlier posts Axtmann has said that when sublimated the crystals reform on the interior of the hive and keep killing mites as the bees/mites contact it. This could still be a contact poison. I use it 3X a week apart in the fall. The kill seems to taper off after a week. A friend used it this year and said it didn't start killing until several days had gone by. Then there were hundreds. Go figure.
Dickm
Sundance,
Membership to ABF for hobby beekeepers is $35.00/yr. Web site is www.abforg.net. Rick
My understanding of the way that oxalic works
is to destroy the "waxy" coating on the chitin
(exoskeleton). Without this thin waxy coating,
there is nothing to stop water loss through the chitin.
The mites die from dehydration, but only if
directly contacted by enough of the oxalic.
This takes time, hence the lag between treatment
and "significant mite drop".
A basic problem is that bee brood areas are
high-humidity environments, kept at a constant
high humidity by the overt actions of the bees.
So, use of a queen cage will make your oxalic
more effective, as a trivial brood area means
a smaller area with high humidity, and a better
kill ratio. (I've said it before, and I'll say
it again - a (nearly) broodless period makes
ANY treatment more effective, and at $2.00 each,
a queen cage is your 3rd best IPM investment,
the 1st and 2nd being, of course, a pencil
and a notebook, as (of course) you cannot
control that which you do not measure.
Bees have more advanced respiration systems,
so they don't "dehydrate" in the same manner
as mites would.
I'd love to see the stuff legalized in the USofA,
but I see no reason to vaporize the stuff given
the encouraging results seen with "drizzle"
applications, as addressed at EAS 2005 at Kent State.
Vaporizers and foggers seem to be weapons systems
that satisfy the cravings of beekeepers to pick
up some sort of "BFG-9000" (The "Big Freakin Gun"
from the "Doom" video games) and use it to make
BIG IMPRESSIVE CLOUDS of stuff. While this
approach may be good for the ego and soul, the
cheaper, quieter, lower-tech approach seems to
work just as well, and is a lot safer and easier
to deploy when one has employees, family, and
friends on the payroll as apprentice beekeepers.
[size="1"][ December 16, 2005, 10:48 PM: Message edited by: Jim Fischer ][/size]
The mite's cuticle (skin) is heavily sclerotized (thickened), which helps reduce water loss. It has a chemical pattern similar to that of the bee's cuticle, which may help camouflage the mite within the bee hive.to destroy the "waxy" coating on the chitin (exoskeleton). Without this thin waxy coating, there is nothing to stop water loss through the chitin.
The mites die from dehydration
Can you be a bit more clear on what you are trying to say here?Bees have more advanced respiration systems, so they don't "dehydrate" in the same manner as mites would.
> Can you be a bit more clear on what you
> are trying to say here?
If you can look up and find terms like "sclerotized",
you can read a little more, and answer your own
questions. I explained the mechanism in clear
and simple terms.
Your sole purpose in the post above appears to
be to "heckle" and argue, not to enhance your
or anyone else's understanding.
Find someone else to bicker at, or better yet,
go get a girlfriend or something.
schlerite: a hard chitinous or calcareous plate.
schleroid: hard endurated
OK, I looked up those terms.
But, this still confuses me, since the bees and mites have very similar chitin:
>Bees have more advanced respiration systems, so they don't "dehydrate" in the same manner as mites would.
What precisely do you mean by “more advanced respriation systems”. Do bees have lungs? How do they "dehydrate"?
>Find someone else to bicker at, or better yet, go get a girlfriend or something.
...and to think just the other day you wished Merry Christmas to everyone on the planet. Are you now rescinding my Merry Christmas?
![]()
>>the
cheaper, quieter, lower-tech approach seems to
work just as well, and is a lot safer and easier
to deploy
What about Axtmanns claim that the liquid application is much harder on the bees, than he found with the vapourizing method?
Ian Steppler >> Canadian Beekeeper
www.stepplerfarms.com
>...claim that the liquid application is much harder on the bees...
During her presentation at the NW Corner Conference in Oregon, Diana Sammataro presented some of what she and another individual were doing in regards to OA. Dr Sammataro mentioned doing several trials with OA liquid.
During the question and answer session, Marla Spivak commented to Dr. Sammataro, that she believed several trials using liquid were harmful to bees.
>>...claim that the liquid application is much harder on the bees...
This may be as simple as suffocating some bees by clogging up their breathing holes with sugar syrup. It's pretty easy to kill bees by drowning them.
It may also have something to do with them ingesting a goodly portion of OA as they clean themselves. I don't know. I've been told you should only dribble OA once a year. This may be the reason.
In any case, I do know that after an OA dribble treatment, you end up with some dead bees- in my case, several dozen or so. Not an earthshaking, devastating loss, but loss far greater than when I've vaporized `em.
George-
Dulcius ex asperis
When sugar syrup with OA is drizzled between the frames with a syringe, it seems doubtful to me that all the bees will be wetted. It does seem to me that more bees will miss being wetted than will actually receive a dosage of OA. The bees that are wetted will be cleaned by other bees and the OA laced syrup will be exchanged with other bees. Hence, my earlier wondering about OA possibly being systemic as some have said. Bees are sometimes drenched with Fumidil by spraying, but they are not drenched by trickling OA between frames, are they?
>but they are not drenched by trickling OA between frames, are they?
Drenched? I'd say not. But I imagine, as they clean themselves and each other, it gets pretty well distributed.
I do recall reading someplace recently about an OA treatment where the bees were lightly sprayed on a frame-by-frame basis.. which would presumably get more bees wetter. Where was that... Oh yeah [img]smile.gif[/img]
http://www.beesource.com/cgi-bin/ubb...2;t=004290;p=1
The say: "Spraying and trickling are done with acid dissolved in sugar syrup."
George-
Dulcius ex asperis
>as they clean themselves and each other, it gets pretty well distributed.
Yes, I'm sure it does, but how much of it actually contacts the mites when bees exchange syrup through trophallaxis, and how much ends up inside the bees?
Just some "food for thought" (sorry George, I just couldn't help that.)
My understanding is that nearly all arthropods, including ticks and mites breath through a trachea system. In addition varroa has an aquatic breathing tube it uses while immersed in the brood food.Bees have more advanced respiration systems,...
So, Jim, wouldnÂ’t that make the mite breathing system more advanced than even the bees. Bees would drown if immersed in liquid.
Help me out here Jim. As another individual sometimes says “Enquiring minds want to know.”
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