Evert

... is functional in food transport. The rest is non-functioning (ref. Esau's Plant Anatomy, 3rd ed. 2006, Chap.14) also (ALFIERI, F. J., and R. F. EVERT. 1968. Seasonal development of the secondary phloem in Pinus. Am. J. Bot. 55, 518-528.) It consists of sieve cells , sieve tube elements , phloem ...

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