he galls of the rose gall wasp (Diplolepis rosae) are also distinctive and are known as bedeguars or robin's pincushions. These are found on the shoots of dog roses and have a length of up to five centimeters with red long-haired outgrowths. Inside the galls are several chambers, which may be occupied by larvae.
Robin’s Pincushion on Rose. Image Courtesy of Bjorn Appel
Knopper galls develop as a chemically induced distortion of growing acorns on Pedunculate Oak (Quercus robur (L.)) trees, caused by gall wasps which lay eggs within buds using their ovipositor. The gall thus produced can greatly reduce the fecundity of the oak host, making the gall a potentially more serious threat than those which develop upon leaves, buds, and stems. The large one inch gall growth appears as a mass of green to yellowish-green, ridged, and at first sticky plant tissue on the bud of the oak, that breaks out as the gall between the cup and the acorn. If only a few grubs are developing within, then it may appear only as a group of bland folds. Where several grubs are competing for space the shape may become much more contorted, with several tightly bunched galls.
Kopper Galls. Image Courtesy of saharadesertfox.
Neuroterus numismalis is a gall wasp that forms chemically induced leaf galls on oak trees. It has both bisexual and agamic (parthenogenetic) generations and forms two distinct galls on oak leaves, the Silk button gall and Blister gall. The galls can be very numerous with more than a thousand per leaf. his Silk button spangle gall has a cover of golden hairs that give the impression of silk thread. The 0.3 cm button-shaped galls have a pronounced concavity and sit tightly against the leaf lamina.
Silk Button Galls on Oak. Image Courtesy of Image Courtesy of Beentree.
Neuroterus albipes is a gall wasp that forms chemically induced leaf galls on oak trees which has both bisexual and agamic generations and therefore forms two distinct galls, the Smooth Spangle gall and Schenck's gall. The normally cream colored saucer of the Smoo