Harvesting cocoons from Corn Quicklock trays is fun. You open two pieces of interlocking trays and you see what is inside. Every row tells its own story and often it is a very different from the adjacent nesting tunnel. It is great to see bees at work, but it is very exciting to see what they have produced and to see what other insects are using these nesting tunnels as their home.
This pink larvae has a brown head capsule. It feeds on any detritus and pollen in the tunnel. If left inside over the winter, it can chew through cocoons and destroy your bees. After it has spun its cocoon, it emerges again during the early summer as a moth. I remove these grubs from the nest as I harvest mason bee cocoons.
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| The warmth of the room where we harvested the mason bee cocoons warmed up the larvae and made it active. It was travelling around the tray as I photographed it. In the foreground are two mud walls dividing two cells each containing a male bee cocoon. The female cocoon usually fills the space between the walls of the nesting tunnel. Each cocoon is covered in frass and some mites. |
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| Here is the larvae spinning its web for its overwintering period. |
Mike
I had these same larvae in my bee boxes this past year with devastating results. Did I leave my cocoons in the boxes too long? I opened the boxes in November to remove the cocoons and at that point most were gone.