Frankfort, Norfolk It was a knobbly red fist of moss-like filaments, grown to completely envelope the unripe husk of a rosehip
When sauntering this path a few days earlier, my eye had snagged on a scrap of bright crimson amid the green hues of the hedgerow. Closer inspection of a tangle of dog rose briars had proven the brazen flash of colour to be a bedeguar gall. The size of a large conker, it was a knobbly red fist of moss-like filaments, grown to completely envelope the unripe husk of a rosehip.
I returned home to books and found that this strange sticky mass had been caused by a tiny wasp, Diplolepis rosae, which lays its eggs in the leaf buds of wild roses. Weeks later the simple feeding of any resulting wasp larvae causes a tumour-like gall to form. Photos of the rarely seen diplolepis showed a tiny amber-legged wasp that reproduces asexually, never needing and seldom producing a male.
Source: Guardian Environment