Weeds are a fascinating study for specialists, not only because of their
economic importance, but also since in this case biology must be
combined with history and agriculture (and its economic aspects). Thus,
weed scientists may be concerned with pure basic research, concentrating
on general aspects, or with applied science, i.e. having a practical
orientation. One of the aims of this book is to create a synthesis
between these two branches of study and to review the literature of both
fields. The agrestals, the weeds of arable land the most important group
from an economic point of view was chasen as the main topic. Other weed
groups could only be mentioned briefly (e.g. grassland weeds), or
superficially (e.g. aquatic weeds), or had to be omitted completely
(e.g. ruderals, because they are so heterogeneous), to keep this volume
to an acceptable size and price. Nevertheless, nearly all subsections of
botanical science have been treated.