The Story of Rosy Dock

As in her previous picture books, Baker (Window; Where the Forest Meets the Sea) uses her exceptional ""collage constructions,"" crisply photographed here, to make an environmental statement. Unfortunately, this volume lacks the hard-hitting impact, both visual and thematic, of her earlier works. ""For thousands of years almost nothing here changed,"" writes Baker of the area around Australia's Finke River. Then come European settlers, among them a woman who ""brought seeds from the other side of the world and planted a garden."" One plant-rosy dock-is a special favorite of this fictional gardener. Seemingly three-dimensional but muted renderings of the riverbed landscape show the area ravaged by cyclical periods of drought and flood, until, after fierce storms, rosy dock ``is spreading like a great red blanket farther than the eye can see."" A cautionary message comes almost as a surprise, in a concluding note: ""Without their normal predators, some non-native plants and animals multiply so quickly they change whole landscapes and push many native plants and animals to extinction."" Young readers, however, are likely to be more troubled by the sudden disappearance of the rosy-dock gardener, last seen huddling on the roof of her home as it is swept along by raging waters. Ages 4-up. (Apr.)