Key to Lichens on Twigs by Pat Wolseley (Pamphlet)

Identification guide to 60 lichens growing on trees and shrubs Designed to be used outside: lightweight, rucksack-sized, splash-proof Photo gallery of each species Accompanying text includes guides to key diagnostic features WildID Lichens on twigs guide will help you identify 60 of the commonest lichens found growing on trees and shrubs in Britain. Every spring deciduous trees produce new shoots, with a new bark surface. In good conditions lichens are rapid colonisers of this new surface. But they must compete with other organisms such as algae and mosses. The mixture of species found will depend on the type of tree, what availability of colonisers and surrounding environmental conditions. Although pollutants can kill many lichens, other lichens tolerate, or even depend on them. This guide indicates which lichens are acid-tolerant and nitrogen-tolerant, and also which lichens grow in unpolluted sites.