Hedgehogs in the rosebushes

Thorns aren’t the only things you can find on rosebush stems. There can also be things that look like small green and red hedgehogs, or spiky cotton balls. They can be as small as cherry tomatoes, or as large as apples. They remain on the roses when autumn arrives and the leaves and flowers all die, but they change colour and become brown. They have the fantastic name of rose bedeguar gall, or Robin’s pincushion and they develop when a small gall wasp lays eggs on the rose stems and tricks the plant into growing the strange or alien growth, that are a combination of lunchbox and bomb shelter for the wasp’s larvae.

The funny thing is that the gall wasp can also be tricked. When it has laid its eggs and the gall has grown, other insects might also move in and lay eggs in the gall, and steal the wasp larvae’s food, or maybe even eat the larvae themselves.

If you want a closer look at what happens inside a gall, then cut pieces of rose stem off in the winter, when they are nice, brown and dry, and take them home with you. If you put them in a jar with a lid on and leave them, the jar will, a few weeks later, be swarming with small, iridescent wasps.