9781422277522

species of small roundworms called nematodes. A cubic foot of soil contains about half a million nematodes. Some are preda- tors, but most are herbivores , eating the roots of the grass. Nematodes need large amounts of food for their size, and com- bined with their vast numbers this means that nematodes, not wildebeest or other grazing animals, are the main plant-eaters in grasslands. In addition to nematodes, grassland soil contains huge numbers of insect larvae , mites, and other tiny organisms. They play an important part in maintaining the grassland, by

What Are Grasslands?

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