Top Entrances and Entrance Shims and Robbing...

[Carriage House Farm]

So, I've built a couple of those Imirie type shims.  I figure this was better than drilling a whole in the box for an entrance.

For those that have top entrances and shims, do you experience robbing?  Or can a healthy hive protect these opening fairly well?

[Michael Bush]

>For those that have top entrances and shims, do you experience robbing?  Or can a healthy hive protect these opening fairly well?

A strong hive in a flow is never a problem.  Any hive in a dearth is a target for robbers.  I ONLY have top entrances so I don't have a problem with two entrances.  I would reduce all entrances in the fall once the dearth sets in but I would leave a top entrance open but small.

[Old Timer]

The Imirie shim is to be used with drawn comb only per George Imirie. He says that if it used with foundation that the bees will connect the frames of the two boxes it is between with burr comb. I've cut some strips down to 3/8" before to use as a spacer between supers for an opening and have learned to not do this unless I use drawn comb. The Imirie shim is a whopping 3/4" and drastically violates bee space. Mr Imirie also suggests to put all your supers of drawn comb,five supers, on at one time before the spring flow and to place one shim between the second and third super and to place another between the fourth and fifth super with a top entrance built into the inner cover. DO NOT USE WITH FOUNDATION WITH THE IMIRIE SHIM. Instead of using the strips for shims, I have a few supers that are dedicated to providing an upper entrance. I cut out a 3/8" strip on the bottom front of the super about 6" wide and place this on the colony above the first super. After that they are alternated to every other super. Works good for me and can be used with foundation.

[Brian D. Bray]

I've taken to building my bottom boards without landing space.  Just make it the same dimensions as the boxes.  I use top entrances so have little problem with robbing.  Too many entrances just confuses things.  No extra ventilation is necessary when top entrances are used in conjunction with SBBs.  If you have problems with the bees building comb between upper and lower frames when using an Imbrie shim I sugguest putting dowling in place.  Make it a slatted rack with an entrance.  Since I use slatted racks instead of queen excluders I don't have that problem either. 

[Zoot]

Oldtimer,

I notice your use of the present tense in relating George Imirie's doctrine; for what it's worth, George passed away this fall.