Dorset, United Kingdom

I grow a variety of ornamental alliums. I have noticed this spring that the leaves of Allium christophii have been munched to the ground by something - almost as if they've been snipped off by scissors! Other varieties of allium have not been affected. Does anyone have any idea what the pest could be? I have the occasional visit by rabbits (seen off by the dog) and there are very few slugs/snails as most are eaten by birds which I encourage into the garden. The beds have recently had a good mulch from the compost heaps - could there be something lurking in that? Have never had this problem before - the bulbs are well established and have increased considerably over the years. Any help would be gratefully received.

• 9 Mar, 2017