How often to apply co2 fo weevil protection

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ekul

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Moved into a new house and for some reason i have weevils everywhere!!! Everything is stored in the garage where i doubt grain has ever been stored before but they are still getting into everything, even though my grain is stored in 20L handy pails. I started freezing handy pails full of grain but it doesnt seem to have dinted it (through cross contamination im thinking).

I've read that giving a burst of co2 kills the weevils off. If i store all the grain in their sacks in steel 44s how often do i need to dose them? every time i do a batch? Once a month.

I like to buy 6 months grain all at once so this problem is doing my head in. Need to restock soon but dont want ot if everything is going to be full of bugs
 
Im not sure if its available for home use, but when grain is stored in silos and bunkers on an industrial scale, they use gas which is alot more toxic than co2 to ward off the weevils. Cant remember what its called but i will find out and come back to you....
 
Matplat said:
Im not sure if its available for home use, but when grain is stored in silos and bunkers on an industrial scale, they use gas which is alot more toxic than co2 to ward off the weevils. Cant remember what its called but i will find out and come back to you....
It is called Phostoxin or similar derivative and it is not available to the public.

An infestation as described by the OP would warrant professional attention.
 
dicko said:
It is called Phostoxin or similar derivative and it is not available to the public.

An infestation as described by the OP would warrant professional attention.

Calling in the pros definitely sounds like the lesser of two weevils.
 
Are you keeping your grain for longer than usual or using a different supplier that may have had old grain?

I have heard that keeping grain or flour for long enough even in a perfectly sealed container you will end up with weevils as the eggs are always there.

Just use it, you probably won't need a protein rest... :ph34r:
 
Give the place a wash bugs don't like the smell of disinfectant.
 
ekul said:
Moved into a new house and for some reason i have weevils everywhere!!! Everything is stored in the garage where i doubt grain has ever been stored before but they are still getting into everything, even though my grain is stored in 20L handy pails. ...
If I was trying to deal with this with CO2, I'd get cut a hole near the top of the bucket, get a grommet (Bunnies) to seal beer line through the hole and enough beer line to reach the bottom of the bucket. This allows you to squirt CO2 to the bottom of the container (I've read a few posts doing this with racking canes, etc), so flush the bucket with the lid nearly closed, plug the beer line outside of the bucket after flushing. Could try with one setup to see if it works first.
 
I'd say they're lesser grain borers more-so than weevils.

Surface sprays won't kill them because they have a hard waxy coating on every body part, so they're impervious to contact sprays.

The most common gas used on them is phosphine, but there's a withholding period and risk of taining if it's overdosed. The population of the little suckers in Australia is also almost immune to phosphine due to cost saving under-dosing at the silo level.

The biggest problem with them is the eggs are there from harvest or storage and they survive malting and drying.

Best solution is to flush with co2 and seal it off......100% co2 in the vessel. That's going to be expensive.

The next best thing is to use diatomaceous earth, made up into a slurry/paste and smear it around inside your drums. If you have stacked bags, then a dusting of DE between each bag and hen a teaspoon inside each vessel mixed through the top 5-6cm of grain.

DE cuts the waxy coating and underlying tissues on their body and makes them die an agonising death within 24-48 hrs. Cuts the population by >75%. Seems fitting. Those that don't die will be rendered susceptible to surface sprays should they cross it on the floor around the grains. Result 100% death.

Combination of co2 flush, Surface spray the walls and floor areas, sealed containers and DE is your best bet. Nuke 'em. :blink:
 
I read that chucking dry ice directly in the grain bag will raise the CO2 concentration to toxic levels as it sublimates. Probably more convenient than stuffing around with your gas bottle if you have easy access to dry ice.

I actually have no idea where one would buy dry ice in Australia. Bait shops? The impression I get from the American forums is that they have it in the supermarket next to the frozen peas or something.
 
Mr. No-Tip said:
Calling in the pros definitely sounds like the lesser of two weevils.
Captain Jack Aubrey fan ?

Had some weevils ( I think ) in an unopened 5kg vac packed bag of weyerman something from craftbrewer that I had sitting @ awhile, cunning german bugs. Also had some weyerman grain ( caraaroma i think ) with a fair bit of "dust" in the bag and a fair few grains that looked hollow yet I couldn't see any creatures ??
Have thought of putting a corny gas post on one of those big plastic olive drums and storing grain that way, take the rats a while to chew through.
Strangely I store base grains in their bags in the small wheelie bins ( full sack just fits) and have not had rat or bug attacks yet.. (jinxed now).
 
I think you can get dry ice direct from BOC....

I think it would get expensive pretty quick though, depending on how often you have to open the container....
 
Moved into a new house and for some reason i have weevils everywhere!!!
Everything is stored in the garage where i doubt grain has ever been stored before but they are still getting into everything/quote]

I think most of you have mis read the OP's problem.

It appears that whatever is infesting his grain is, and has been present in his new home.

I think he should be contacting a proffesional.

If he wants to buy 6 months worth of grain at a time and store it without having his house treated and the infestation eliminated then the problem will always be there.
It is extremely important that the type of insect that he has is identified properly before any treatment is commenced.
 
Buy 6 months worth of grain and and brew it in one hit..
No more grain just beer, no problems! :D

Mark (MHB) used to dose his stock with tablets i believe. Was it Sulphur? (sorry Mark if im wrong)
Im sure some of the larger HBS have similar issues and may have some pointers as well.
 
ekul said:
Moved into a new house and for some reason i have weevils everywhere!!! Everything is stored in the garage where i doubt grain has ever been stored before but they are still getting into everything, even though my grain is stored in 20L handy pails. I started freezing handy pails full of grain but it doesnt seem to have dinted it (through cross contamination im thinking).

I've read that giving a burst of co2 kills the weevils off. If i store all the grain in their sacks in steel 44s how often do i need to dose them? every time i do a batch? Once a month.

I like to buy 6 months grain all at once so this problem is doing my head in. Need to restock soon but dont want ot if everything is going to be full of bugs
The problem with the co2 is that it must go thru all the grain to remove the oxygen. Even if you do get it thru the grain the weevils leave and will then return unless you have it sealed like a vacuum and then work in the Co2. I found it only sends them everywhere and then they return to the ton or two tons of grain in the totes. Check to see if who you purchased it from has a feed sale license. There are samplings that must be taken if tons purchased and no live weevils can be in the large samplings. I believe a certificate is issued to verify this from the farm. Contact you local agriculture department for more information if the seller does not take back the grain.
 
squirt in the turns said:
I read that chucking dry ice directly in the grain bag will raise the CO2 concentration to toxic levels as it sublimates. Probably more convenient than stuffing around with your gas bottle if you have easy access to dry ice.

I actually have no idea where one would buy dry ice in Australia. Bait shops? The impression I get from the American forums is that they have it in the supermarket next to the frozen peas or something.
www.youtube.com/watch?v=tLNHDxd6nDc
 
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