[Tilted Irish Kilt]

djf: " Interesting that in this case their nest is directly below a bunch of wooden blocks that my mason bees are in. (and starting to emerge)"

The mason bees are well known and reverred for pollinating garden and orchard crops , and not known to sting.
Bumble bees are not reverred so much as they will pollinate more ground crops (ie: strawberries, clover ,, blueberries, etc.).
Also , bumble bees will fly in cooler temps ( as cool as 37 degrees), and even later into the night than conventional bees (ideal for earlier crops, and earlier flowers).
Unfortunately , my expierience is more with 'three-banded Italian' and 'caucasian' bees in Langstroth frames .

[fivecatsandadog]

Ooooh, those Italian bees! The former Mr. Fivecatsandadog kept bees and the Italians would chase me all over the yard, right up to the back door - and then hang around waiting for me to come back outside.