The several objectives of this book can be stated in the form of simple questions. What can we conclude about the nature of grass seed dormancy in a single, well–studied, species? Are there commonalities between seed dormancy in this single species and other grass species? Can new conclusions be reached about the nature of the physiological and environmental conditions that establish the state of dormancy in grass seeds? Is it possible to describe new models for seed dormancy that simplify our understanding of grass seed dormancy?

The nature of the first question is in part a semantic problem related to correctly matching the etymological meaning of a word to the reality it attempts to describe. The English word ‘dormancy’, derived from the French dormir (to sleep), itself derived from the Latin dormire (to sleep), is defined in the Concise Oxford Dictionary as ‘lying inactive in sleep’. However, biologists have found that this definition does not encompass observed seed behaviour. Hence the many attempts to divide dormancy into sub–categories that cover the situations in nature where some seeds fail to germinate, whereas others can, in a specific environment (Amen, 1968; Bewley & Black, 1982; Lang et al., 1987).

An adequate description of dormancy must involve at least three major components viz. the seed, the environment and a time element describing changes in state of both the seed and environment. In addition, it is useful to have some measure of incidence of dormancy related to genetic variation in a plant population.