For the 126 taxa covered in the book under review
(itself 13 years in the making), information is given on the world
geographical distribution (i.e., maps show countries, or
portions thereof for large countries, where they have been reported
as weeds) and habitat, ecology and biology [including morphology,
physiology, life cycle type(s), propagation and reproductive biology,
dispersal, etc.], and agricultural importance. For some
species, one or more of the following topics also is(are) discussed:
herbicide resistance, taxonomy, anatomy, utility, chemistry and
toxicity, host relationships (for parasitic plants), and biological
control. A list of common names by country is given for each
taxon. The book contains a glossary of 236 terms and a bibliography
of about 3300 references.
Within the group of 126 weeds covered in World Weeds, there are great differences in geographic range (e.g., tropical vs. temperate), habitat, ecological tolerances and requirements, growth form, life cycle type, and physiology. From a taxonomic/phylogenetic point of view, the list consists of a disparate group of plants, which includes ferns (Azolla, Marsilea, Pteridium), dicots, and monocots. Most of the species are herbaceous, but a few are woody. There are many contrasts in species biology among this group. Twenty of these are: (1) annuals/ephemerals (reproduce by seeds only) vs. perennials that reproduce by both seeds and vegetative propagation; (2) one generation per year vs. more than one generation per year; (3) monoecious vs. dioecious; (4) single-season- vs. year-round flowering; (5) wind- vs. insect pollination; (6) agamospermy vs. sexually-produced seeds; (7) autogamy vs. self-incompatibility; (8) production of many- vs few seeds; (9) production of large- vs small seeds; (10) wind- vs. animal dispersal of seeds/fruits; (11) physiological- vs. physical [hard seed (or fruit) coat] dormancy of seeds (or fruits); (12) small- vs. large soil seed bank; (13) single short germination season vs. year-round germination; (14) autotrophic vs. heterotrophic (holoparasites); (15) photoperiodic control of flowering (SDP, LDP) vs. day-neutral; (16) C3- vs. C4 pathway of photosynthetic carbon fixation; (17) N2-fixing vs. not N2-fixing; (18) mycorrhizal vs. non-mycorrhizal (e.g., Brassicaceae, Cyperaceae); (19) good- vs. not-so-good competitive ability; and (20) allelopathic vs not allelopathic; there are others.
Thus, it is not obvious to this reviewer that a common "thread" runs through the autecological characteristics of this group of plants. However, (1) many of the species are highly variable (e.g., cytologically, morphologically), (2) most appear to be autogamous, and (3) the great majority appear to be able to form a persistent seed bank. Apparently, some combination(s) of life history and ecological characteristics "bestow(s)" weediness on this group of plants (e.g., see Baker 1974).
Holm et al. have done an impressive job of assembling and summarizing the huge amount of literature on the biology of the 126 species covered in World Weeds. This book is a mine of information on the biology (in the broad sense) of weeds that will be useful to both basic and applied scientists working on weeds at the whole-plant level and/or at a higher level of biological organization. Further, World Weeds is a great source of information for students in, and instructors of, weed biology and plant autecology courses. However, the very high cost of the book probably means that few individuals (and some libraries, especially those in third-world countries) will not be able to purchase a copy of it. - Jerry M. Baskin, School of Biological Sciences, University of Kentucky, Lexington, KY 40506-0225.
Literature Cited: