Third edition. This wonderful little book covers everything you need to know about the types of plants known as weeds. Ehrenfried Pfeiffer discusses the different varieties of weeds, how they grow and what they can tell us about soil health. The process of combatting weeds is discussed in principle as well as in practice, so that it can be applied to any situation. First written in the 1950s, this is still one of the best overviews of the subject available.