Bees do build nice colonies in cinder blocks and/or 88's fwiw. Have taken out many in past, but in doing so used a pickax and sledge hammer to get to bees....along with cement cutting blade in circular saw taking time. For you cut the groove first and then with pick ax and sledge hammer then take out the cement as best you can....
But they do go up and down the insides of the blocks and perhaps reason why some many nowadays are filled in with cement and foam anymore, so no space available.
Dee A. LUsby
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