Word: shortleaf
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Dates: during 1980-1989
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Another clue comes from a study of 7,000 trees, sponsored by the Environmental Protection Agency. Scientists at Oak Ridge National Laboratory in Tennessee examined 14,000 core samples of the tree trunks. Their findings: beginning in 1960, in eight Eastern states, pitch and shortleaf pines and red spruce started to show narrowing growth rings, a sign of sluggish development. Similar changes have been noted in West Germany's stricken trees...
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