Screened Bottom Boards for ventilation & controling pests

As I’m sure most of you are aware we have opted for including screened bottom boards as part of the full flow hive. Here is a good article advocating the use of screened bottom boards especially for the Australian climate.
http://www.rirdc.gov.au/news/2014/12/09/screened-bottom-boards-provide-varroa-management-option

They are great for helping control many pests. On top of the plastic board that you slide under the hive we have been using cheap plastic table cloths upside down (they have a fluffy felt like back on them) stuck there with double sided sticky tape. The small hive beetle fall through and get tired and stuck trying to crawl out, eventually dying. This method avoids using oil or water which can fester.

So it seems like only a good thing to use screened bottom boards in Australia. What are peoples thoughts on them for colder climates?

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Jake, I noticed the meshed bottom boards under your display hives at Byron Bay last week. Is there a local Australian supplier for this mesh? I’m building a non standard sized hive and I need the mesh rather than assembled bottom boards. In the USA, 1/8 inch galvanised mesh is widely available, sold as “hardware cloth”. In Australia the choice seems to be woven flyscreen with apertures up to 2mm, or snake and rodent welded fabric with an aperture of 6mm. The ideal mesh aperture appears to be somewhere between 3 and 4mm. Our Aussie rodent mesh is too big and our flyscreen is too small.

The screened bottom board fad is fading fast in my area.They can’t support as much weight; waste, debris, insects, and other pests get between the screen and the area under the screen where the bees can’t clean it out. I have 4 more screened bottom hives to change out and then all 40 will be solid bottoms.

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G’day Ed, I’m with you. I’ve never used one. A few of the hives I manage for a bloke had thin slots on the bottom (aluminium) board with oil trays beneath. I think (well,I do know) that was to control SHB. I removed the oil trays & filled the slots with plastibond. The bees will get rid of anything they don’t want through the entrance. I control SHB without any traps/lures/pesticides whatsoever.

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I started off with them when they were all the rage, discovered they don’t have any benefit, and am going to all solids. Trees don’t have screened bottoms nor do cavities in buildings lol.

No Ed:) that’s for sure.

I have had a look in some local hardware stores but it seems none have it in the right specification. I’m not sure who is supplying us in Australia but if you have a local stainless steel fabricator you might get lucky or you could ask them to order you some. Other wise someone like this may be able to post some:
http://www.sswm.com.au/Stainless-Steel-Woven-Mesh

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Wandering what you use to control SHB? I know when a hive is healthy they have the numbers to control them them selves. At the moment I have just installed a package and the numbers are still building up and there seems to be a lot of SHB everywhere in the northern rivers at the moment. So I have found it great to be able to pull the bottom board out regularly and see the beetle activity and squish them.

Hi Jake, I’m sure they are just as bad up here. Now the trick is: If you only have enough bees to cover, say 4 frames. The bees will do that, they will congregate in as many frames as they need & protect those frames. If you have enough workers to cover 4 frames, they wont spread themselves thinly over 8 frames. Any excess frames that are not covered in bees must be completely free of pollen or brood. Dry stickies or foundation is fine, the beetle wont lay eggs on those. My main strategy gets a bit of flack on this forum, it’s keeping the drone population down. You don’t want any large areas of drone comb on your frames. Lots of small areas is better than one or two large areas. The beetle find it easy to lay eggs on drone comb because it’s unprotected by workers. Drones WONT do any defending or chasing beetle into hiding places… To summarize an answer to your question. A weak colony can protect against shb just the same as a strong colony. The key is not to have any food that the beetle can lay eggs in that is unprotected. …It’s also prudent to make sure there’s nothing laying around outside the hive that beetle can lay eggs in. PS, My observation hive is weak in numbers, only 3 frames, there is always beetle hiding under the lid, but the bees wont let them lay any eggs. Good luck with everything, cheers

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I’m in the Northeast, zone 7a:
I used to use beetle traps installed between the frame tops in the hives. I’d bait them with a little mineral oil and apple cider vinegar. They would catch beetles.
After reaching the 40 hive mark and listening to the advice of our state bee inspector, I started not trapping beetles this year. As this season finishes up, none of my hives got over-run with beetles; weak ones, strong ones, it didn’t matter. I’m thinking that using the beetle attractant was :open_mouth: attracting beetles.

I found that but rater than get rid of the screen (which I like) I put my boxes on an open hive stand so that the screen is open to the ground. Rubbish falls to the floor. I also deepened the floor so that an extra inspection tray can be put underneath, leaving a gap of some 10cm twixt screen and tray.
I can leave this in as long as I want. I can see where the bees are in winter and where the brood nest is without opening the box. It just needs a wipe regularly.

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I think you will find that is Varroa Jeff not SHB.

“Female beetles lay irregular masses of eggs in cracks or crevices in a hive. The eggs hatch in 2–3 days into white-colored larvae that will grow to 10–11 mm in length. Larvae feed on pollen and honey, damaging combs, and require about 10–16 days to mature. Larvae that are ready to pupate leave the hive and burrow into soil near the hive.”

Generally in the dark corners. Varroa on the other hand lay in Drone comb but not exclusively

Beetles will lay in cracks and crevices BUT also directly on the comb and even pierce capping to lay into cells.
Drone comb is more likely to be at the bottom of the frame (in a foundation-less set up) or at the periphery of the brood nest where it is indeed less policed by worker bees so Jeff’s notion of reducing drone comb to help reduce the numbers of SHB may indeed have some worth.

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Valli, your speaking from what you read, I’m speaking from nearly 16 years of experience. SHB arrived here in the year 2000. I’d nearly call myself an expert on SHB. @Jake can either take my advice or ignore it, it’s entirely up to him. Or anyone else for that matter. One day I had to tell a bloke to take a holiday from worrying about SHB, I told him to do what I do. He finally took my advice & it works for him.

@JeffH
SHB is in Italy, notifiable but judging by the paucity and timing of reports beekeepers are not reporting it until harvests are in. It hasn’t a hope of being contained and will come to the UK where some beekeepers will be overwhelmed…they can’t manage varroa and nosema, for heaven’s sake let alone the hotspots of foul brood associated with commercial packaging plants. I suspect many hobbyists will give up. We need all the help we can get so thanks for sharing what works for you

Hi & your welcome, thank YOU Dee, SHB do best in hot humid conditions, I’m doubting if it will ever be a major problem in the UK. On the other hand, if they get into hives, the hive temp would suit them. Michael Bush says they’re in his area of Nebraska, which I think gets very cold. I’m sure that beekeepers in Florida have more trouble with them than beekeepers in the north… They will breed up in slumgum. They grow fat & juicy in slumgum. I can leave slumgum uncovered all through winter & a month into spring without any activity. After that I have to seal it in buckets. That’s why part of my strategy is to not leave anything outside the hive laying around for them to multiply in. Anyway our noses let us know if any activity starts before they reach maturity & pupate in the soil. I found the best way to kill any larvae infested stuff is sealed in a bucket in the sun.

PS, I just did some checking, the UK is roughly 10deg further N. than Italy. I’m wondering if beekeepers in Southern Italy are having more trouble with SHB than in the N. of Italy.

Yes, indeed. Reports are from Calabria, which is the "toe"
Most of the UK has temperatures too low for successful pupation but the south is at risk potentially.
Equally, heavy soil should protect us beekeepers on northern and western clay.
We are awaiting Asian hornets too…
Not easy, this beekeeping is it?

No, your absolutely right, it’s not easy. I told a bloke the other day you could fit the basic rules of beekeeping on a piece of note paper. Then there’s all the bits & pieces in between. The main thing is to know how to recognize a small problem & remedy it quickly before it ends up a big problem.

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Thanks for your feed back folks. I think I will continue using the screened bottom boards and if the hive beetle numbers build up too much I’ll look at following your recommendations @JeffH. I’m a bit of a believer in the lazy approach to beekeeping and not interfering too much with the hive. I feel like leaving them to create drone comb as they feel fit is fine, if there are issues arising from the drone population I’ll then intervene. I know Michael Bush recommends allowing the bees to create comb as they please.

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