Another unusual requirement for germination of some seeds is the need to be scarified by fire. Obviously, such extreme measures apply only to seeds with very thick coats and are most common among species living where periodic lightning-caused fires are a part of the balance of nature. In Mediterranean-type climates, including the American Southwest, a group of plants is classified under the name chaparral. These are low-growing shrubs bearing small, leathery leaves, rich in highly flammable resins. Their leaf litter and dry branches make perfect tinder for fast-moving fires, especially on the
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