Gall-inducing insect Gall-inducing insect A gall-inducing insect is any insect that can cause the growth of galls within plants. The term gall fly is also used to cover these species, although most are not true flies. There are several groups of insects that meet this description. They include the gall wasps, scales, gall midges, aphids, psyllids and certain species of leafminer flies. Galls are growth deformities induced in certain plants by various insects which are mostly species-specific. The gall's form or type depends on what organism is attacking the plant and where the plant is being attacked. Based on the form, there
Velvet industrial power looms became available, and well-made velvet remains a fairly costly fabric. Velvet is difficult to clean because of its pile, but modern dry cleaning methods make cleaning more feasible. Velvet pile is created by warp or vertical yarns and velveteen pile is created by weft or fill yarns. Velvet can be made from several different kinds of fibers, traditionally, the most expensive of which is silk. Much of the velvet sold today as "silk velvet" is actually a mix of rayon and silk. Velvet made entirely from silk is rare and usually has market prices of several hundred