Forests can be found all over the world—including underwater! Giant kelp forests grow in coastal areas where the water is so clear that sunlight can reach the sea floor. Kelp can grow more than a foot in a day if the conditions are right, meaning kelp forests spring up quickly. Full-color photographs and accessible language take readers under the sea to discover an extraordinary habitat. Information about photosynthesis and algae structures supplement readers' knowledge from science class. Fun fact boxes give budding marine biologists even more interesting information about kelp and its critical role in the ocean biome.