Gloucestershire, United Kingdom

What is this bug 2?
The other day I was clearing out some redundant pots mounted on un-mortared brickwork only to find a pot fixed solidly to the top course of bricks with some difficulty I managed to remove the pot from the brickwork and finding beneath a maze of white cotton like material that had the effect of sticking the pot to the bricks thinking I
Should clean off the white stuff I attempted to lift a brick only to find my hand come away with no brick lifted, and sore fingers from trying to lift more than the expected weight: eventually I managed to separate the bricks with a hammer and cole chisel finding more white stuff with tunnels in it, occupied by what I can best describe as long maggots in them. I have since been told that this was done by a moth of some sort, my question is What sort of moth was it? If the strength of the glue was any thing to go by the moth its self must be mighty ferocious.
That apart, my main question is of another bug or rather the occupations of another bug I have encountered. In re-potting a cactus I found a rather large tunnel running along the side of the pot and root bowl, the tunnel was blind and empty, thinking it may be a slug run I checked around the root bowl for slugs only to find another tunnel (rather large) tracing this tunnel I eventually found a green leaf sprouting deep inside the bowl: with a pair of tweezers I pulled on the leaf that came away with no roots on it and the bottom end though dead appearing to have been cut with a pair of scissors, delving further into the tunnel I found a bud of some sort that had, as I’ve said appeared to have been cut with a pair of scissors. Removing the bud I began unfurling the leaves from the bud to find inside a dead leaf in the centre full of very soft balls obviously eggs of some sort. Question what size/type of creature pulled this bud up the side of the pot after excavating a tunnel in which to place it, any answers welcome. Thanks

• 11 Jul, 2011