bedeguar gall

A gall is a localized swelling or outgrowth of plant tissue. These abnormal growths are typically caused by the irritation or infection from various organisms, including bacteria, fungi, viruses, nematodes, insects, and mites.1

A specific type of gall is the bedeguar gall, which appears as a moss-like growth on rosebushes. These are produced by gall wasps, such as Rhodites rosae.2

Gall flies are insects that induce these galls. When a female gall fly lays an egg in plant tissue, the hatching larva releases substances that stimulate the plant tissue to grow around it, forming the gall. The gall provides a habitat and food source for the developing larva. Different insect species create distinct types of galls, often characteristic of that species.34