Rose bedeguar gall (Diplolepis rosae)

On my way to work this morning I noticed a Rose bedeguar gall, so I thought I would tell you all about it. What it is is a sort of ball of hairy growth found on rose plants, in this case I think it was a Dog Rose in the hedge row.

Apparently they are created by a type of wasp called  the gall wasp (Diplolepis rosae), they lay eggs in the leaf buds and when the larvae (almost all female) hatch and they start to eat the leaf bud then some magic happens. It is not full understood but it is belived that a chemical is realesed that causes the plant to grow in the strange way it does, which provides more food for the growing larvae.

The fully developed gall was used in days gone by a a medicine, to cure baldness, and cure a toothache.

If you want to know more why not check out Wikipedia. Picture blow show a new one from this year and an old one from a previous season.

Gall wasp new
Gall wasp old