Galls and Sunshine

Unusually for a Bank Holiday weekend, the weather has cheered up and this morning was bright, sunny and warm as we set out for our walk expecting to be annoyed by too many cyclists and others. We were very pleasantly surprised to find that the good weather had probably sent most people away for the day, leaving Shipley Park strangely quiet. As we stood at 'Vole Bridge', we looked out across what used to be the Nutbrook Canal, now filled with reeds.

The old canal sweeps around the field and into Mapperley Wood in the distance and is now under the jurisdiction of the Derbyshire Wildlife Trust, who seem to be doing an excellent job creating habitat for flora and fauna.

Nearby, the herd of White Park Cattle which are normally to be found grazing close to Head House Farm, were enjoying a change of scenery in a different field. This mother and her two calves were certainly happy to 'sunbathe' and have their photo taken.

The various beasts of Shipley Park are not all as large as the Cattle. Some, much smaller ones, have been making their mark on the Oak trees hereabouts in the form of the many different types of Galls to be found at the moment. We started with the well-named Artichoke Gall.

These galls are produced by the Oak in response to an egg, laid in a leaf bud by the gall wasp Andricus fecundator.

A small, asexual wasp will appear from the gall in Spring and lay eggs in the developing Oak catkins, prompting the tree to form another type of gall. This will, in turn, give rise to a sexual generation of wasps which mate and lay eggs in the leaf buds again, so completing the cycle.

Another Gall appearing in great numbers at the moment is the Marble Gall. These are about the size of a cherry, hard and brown and grow on the stems of the oak as a result of another Gall Wasp.

This time, the culprit is called Andricus kollari. This gall wasp needs two different species of Oak to complete its life cycle. The Pedunculate Oak (as in this case) or Sessile Oak which host the marbles containing the asexual generation, and the Turkey Oak which host the developing sexual generation of wasps.

Not all the Galls in our hedgerows are to be found on Oak trees. The Dog Roses too, host some particularly fine galls often called Robin's Pincushions.

Caused by the gall wasp Diplolepis rosae, the name 'Robin' comes from an association with an old English Folkloric character known as 'Robin Goodfellow' - the same character who is referred to as 'Puck' in Shakespear's Midsummer Night's Dream.