tiddyoggie wrote:
A fellow gardener potted on some brassica plants which he had brought
on in his greenhouse. The plants had grown to 5/6 inches in height
and were in 3 inch modules. A few days ago he found that some of the
plant stems had been cut/severed, but there was no sign of the
missing stems and leaves. Later on, he found the stems and leaves
intact, not having been nibbled, in a gap under a tray adjacent to
where the plants were. They had obviously been carried there by the
culprit, but left untouched! He has mousetraps set, but I do not
think that mice tamper with brassicas, and would not in any event
transport them to a "store". There is no sign of slug damage.

Baffled. Any ideas?

I would suggest rodents are likely, if hungry they will eat almost anything.
Look for scats to identify the unseen. You don't say where this is so there
could be other critters who act the same way, including those on two legs.
Slugs and cut worms etc are not so tidy.

David