Mildew in my hives

[WhipCityBeeMan]

This year I made the move to screened bottom boards. The area where I live and keep my bees is close to a wetland so the ground is always damp in my back yard.  There isn't standing water or anything but evenly moist soil.  I have noticed that  the inner covers on my hives and on or two of my covers have developed mold on them.  I am assuming this is because more moisture is getting in the hives from the ground through the screened bottom boards.  Then as the sun warms the hives, the mold develops.  All my hives are elevated 16" off the ground.

My questions are as follows:

1)  Has anyone else had this experience? 

2)  Are there remedies other that relocating my hives?  Perhaps increasing ventilation through the top of the  hive?

3)  How concerned should I be?  There is not mold everywhere but my gut feeling is that I need to improve the situation. 

Thanks for you help.

-Whipcitybeeman

[Moonshae]

Are the bees adequately filling the space you have provided, or do they have too much space? If they have more space than they can manage, they won't be able to keep it clean. This sounds possible.

That said, increasing ventilation by adding a top entrance, or just propping up your cover will probably be enough, if the space is appropriate to the population. Put a stick between your inner cover and the top super, and the bees will have an extra entrance and more ventilation. If the population is small, though, adding an extra entrance could be a problem, because it's more space they'll need to defend. Base your decision on the population in the hive.

[DaveKow]

I was thinking some type of vapor barrier on the ground beneath the hive. 

[Brian D. Bray]

This year I made the move to screened bottom boards. The area where I live and keep my bees is close to a wetland so the ground is always damp in my back yard.  There isn't standing water or anything but evenly moist soil.  I have noticed that  the inner covers on my hives and on or two of my covers have developed mold on them.  I am assuming this is because more moisture is getting in the hives from the ground through the screened bottom boards.  Then as the sun warms the hives, the mold develops.  All my hives are elevated 16" off the ground.

My questions are as follows:

1)  Has anyone else had this experience? 

Yes.

2)  Are there remedies other that relocating my hives?  Perhaps increasing ventilation through the top of the  hive?

you need top ventilation and more bees filling the space.  In a hive without adequate ventilation and not having bees on every frame mold will form on those frames not covered by the bees.  Once top ventilation is provided and the hive filled with bees the problem will correct itself as the bees will clean out the mold.

3)  How concerned should I be?  There is not mold everywhere but my gut feeling is that I need to improve the situation. 

Thanks for you help.

-Whipcitybeeman
[/quote]

See answer #2.

[wayseer]

As a matter of interest - what's a screened bottom board?  We don't have such in Australia.

[WhipCityBeeMan]

A screened bottom board is a bottom board where the bottom is made from a screen.  It is an integrated pest management technique that allows varroa mites to fall through the bottom of the hive.  It is usually used along with powdered sugar treatments for varroa mite. 

http://www.honeycouncil.ca/users/folder.asp?FolderID=4924

http://en.wikipedia.org/wiki/Varroa_destructor

[wayseer]

Thank you.  Fortunately Australia is varroa free - for the time being at least.

[Michael Bush]

>1)  Has anyone else had this experience?

Yes.

>2)  Are there remedies other that relocating my hives?  Perhaps increasing ventilation through the top of the  hive?

More ventilation might help, but higher ground and full sun will make a much bigger improvement.

>3)  How concerned should I be?  There is not mold everywhere but my gut feeling is that I need to improve the situation.

You will probably have a lot of chalkbrood as a result.