I have an infestation in my Aquilegia patch. The leaves are gone and
what remains are the stalks and a few tough bits. It would seem that
one of the Sawfly family has paid me a visit.

I have had picked 3 caterpillars from the plants (about 30 plants) but
I suspect there are many more, but they are just so difficult to spot.

I read that Aquilegias can be cut down to the ground in preparation
for the winter and will grow new leaves etc in the spring. Would it
be worth trimming these plants back to ground level, there by removing
the food supply and hopefully eliminating the caterpillars?

These are new plants raised from seeds this year so I would not class
them as 'established'.

Look forward to reading any advice.