This book introduces the community of insects that make their home on thistles, feeding on the leaves, the flowerheads, the roots, the stems, or each other. It deals with creeping thistle and spear thistle. Because thistles are introduced to countries outside Europe, the insects that feed on them in Britain are of interest as potential biological control agents. This book describes the natural history of the important groups of insects, and shows how to find them and how to observe their lives. It discusses the effects of herbivorous insects on the plant, and the impact that they may have in biological control. The colour illustrations show the major insects, and there are keys for the identification of the characteristic thistle-dwelling insect species. Much remains to be discovered about these creatures, and the book draws attention to topics suitable for further investigation. Techniques are described.
Introduction; The resident fauna of thistle heads; Stem-borers and leaf-miners; Insects on the outside of the plant; Insect herbivores: biological control; Identification: Key 1 Arthropods inside thistle heads; Key II Insect larvae and pupae inside stems and roots; Key III Insects larvae and pupae in leaves; Key IV Insect adults, larvae and pupae on the outside of the plant: IV.1 Hemiptera adults and nymphs; IV.2 Lepidoptera adults; IV.3 Diptera adults; IV.4 Coleoptera adults and larvae; Techniques; References and further reading; Index.