On 13/08/2020 15:20, Another John wrote:
We have a very large wasps' nest inside the eaves of our roof - football
size. (My question is at the end of this message.)

Football-size is average by wasp standards.

I've repeatedly sprayed it with the excellent Rentokil "Wasp Nest
Destroyer", but inside the roof space I can can only see (and therefore
spray) the inside half of it -- the rest is buried right into the eaves.
I cannot get nearer to it than about 3 metres (and in any case I don't
want to!).

It is best to spray the entrance to the nest in the late evening when
the wasps are in it. Of course, that is the most difficult time to see
what you are doing!

I put up the ladders to the gutter, and tried to spray between the gaps
in the tiles, where the buggers are getting in, but the spray clearly
doesn't reach: they must have a walkway up to the nest,and the poisonous
foam must be dissipating before hitting any part of the nest.

Definitely inadvisable. If the wasps feel threatened they will attack en
masse. Being up a ladder when they do is not the best place to be.
After a week of trying repeatedly (three cans of Destroyer used!), I've
had to call quits.

My question: will winter kill this nest and all its inhabitants, or am I
going to have to call an expert?

Wasps do not return to a nest they have made the previous year. A queen
leaves to start a nest elsewhere. Any remaining wasps will die over winter.

--

Jeff