I don't know about bees, cause they aren't much of a problem around here, but I do know about yellow jacket wasps (really bad problem in my area, and I'm VERY allergic). During this time of the year, they are most active from 9am - 8pm, and are most aggressive from 3pm-8pm, mainly because they change their diet end of summer/beginning of fall. Now they are eating more rotten fruit. Rotten fruit contains alcohol, and towards the end of the day they are drunk, confused and mean.