this morning it's not a "congrgation spot" anymore, there are sick & dead bees all over, upside down unable to fly.
Varoa maybe? 2 days ago I did an inspection, but I wasn't looking for varoa... I have screened bottom boards and sprayed the trays with oil in april when I put my hives together. Maybe not enough oil or maybe I need to clean them more often. They are covered in debris, I'm unable to detect mites. I'll take a look in the hives, especially look at drown cells I read today...but what I read seems tricky in removing infested cells.
On 6/1 TruGreen pesticide was spot applied to lawn about 30 feet away.
Today's count is probably over 100 dead or suffering bees.