VTBeeHannah · Vermont, US · Pests & Disease · Jul 8, 2026

Chalky white lumps AND weird curled larvae in the same hive — chalkbrood or sacbrood or both?

Vermont, second year, and my weaker colony is throwing two different kinds of gross at me and I can't tell what I'm looking at. Thing one: hard white and some grey-black lumps in a few cells and a couple on the bottom board. They're solid, almost like little pieces of chalk, and rattle if I shake the frame. Thing two: a few larvae that look like sacks of fluid, lying stretched out in the cell with the head end dark and curled up toward me. Someone on another forum said 'chinese slipper' and honestly that's exactly the shape. Are these the same disease at different stages or two different problems? And how worried should I be — is this a burn-the-hive situation or a shrug situation? Colony is otherwise okay, maybe 6 frames of bees.

#chalkbrood#sacbrood#brood-disease#diagnosis

▲ 12 votes 💬 4 replies ✅ Solved

4 replies

ImkerinLena · Jul 8, 2026 · ✅ Accepted answer

You've described both, and identified them correctly. Hard rattling mummies = chalkbrood, a fungus (Ascosphaera apis). Fluid-filled larvae with the dark upturned head, the chinese slipper = sacbrood, a virus. Neither is a burn situation — that's AFB, which looks completely different (sunken perforated cappings, ropey brown goo). Both of yours are stress diseases with no chemical treatment: reduce damp, strengthen the colony, requeen if it persists. Bees dumping mummies on the bottom board is a good sign — they're cleaning house.

PasiekaOlek · Jul 8, 2026

Had chalkbrood in a damp out-apiary two springs back. Tipped the hives slightly forward so rain ran out the entrance, moved them into morning sun, gone by July. The mummies look scary but it's the most fixable disease we get.

InesMel · Jul 8, 2026

One add: sacbrood usually burns out on its own in summer, but if you keep seeing slipper larvae into August, requeen without sentimentality. Some queen lines just throw susceptible brood year after year.

VTBeeHannah · Jul 9, 2026

Huge relief, thank you. The hive IS in the shadiest, dampest corner of the yard — moving it to the sunny side this weekend and I'll watch for the slipper larvae through August. So glad it's not the ropey one.

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