For the first time, researchers have deciphered the DNA code of a tree. This accomplishment makes the black cottonwood, a type of poplar, the third plant species whose genome has been sequenced.
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Since 2000, scientists have spelled out the long string of DNA components for rice and Arabidopsis, a plant in the mustard family that’s commonly used for genetic experiments (SN: 9/3/05, p. 157: Available to subscribers at Rice, revealed; 12/16/00, p. 388: First Plant Genome Thrills Biologists). But because both these plants are herbaceous, they are missing some genes found only in trees and other woody-stemmed plants.