Plant Galls & their associated communities

This page is dedicated to my interest in plant galls - primarily Oak Galls, caused by Galls Wasps (the Cynipids).

Cynipid Galls
Galls on Oak (Quercus spp.)

Knopper Gall (Andricus quercuscalicis) [photo courtesty of Geoff, aka. 'Blade Runner']. First recorded in the UK in the 1960s this species has spread rapidly across the country. It is now one of the commonest Oak galls all across England. When it first appeared many people thought it would wipe out the English Oak but, although they probably have some effect, when put into context and compared with other problems like deforestation caused by agriculture and building, it isn't all that significant.
  Marble Gall (Andricus kollari).
  Oyster Gall (Andricus anthracina).
  Cola-nut Gall (Andricus lignicola).
  Turkey Oak Gall (Aphelonyx cerricola). This is one of our most recent introductions, having been first discovered in 1997 near Maidenhead, Berks. Since then it has been found in Windsor Great Park and in Ascot.
Red Currant Gall (Cynips divisa) with a parasitic wasp (Torymus sp.) ovipositing into it. The galls mature throughout the summer and during their development they are constantly at risk from parasitic wasps like this one. The parasite uses its long, thin ovipositor (egg-laying tube) to lay its eggs inside the body cavity of the gall wasp and it is consumed slowly from the inside out.
  Common Spangle Gall (Neuroterus quercusbacarum).
  Silk Button Gall (Neuroterus numismalis).
  Smooth Spangle Gall (Neuroterus albipes).
Oak Apple (Biorhiza palida) with a parasitic wasp on it. Oak Apples are soft, pithy galls that appear in Spring, as the leaves are breaking, and usually remain on the tree until autumn.
Galls on other plants
  Robin's Pincusion (Diplolepis rosae).

Mite Galls
Nail Galls on Lime (Tilia sp.) [photo courtesty of Geoff, aka. 'Blade Runner']. Galls like these are quite common on a variety of plants. The upper surface of the leaf sprouts a small fleshy bump and on the underside there is a small, hairy dent - where the mite lives.