University of California

The phloem of the sweet orange tree trunk and the seasonal production of xylem and phloem


Henry Schneider

Author Affiliations

Henry Schneider was Assistant Plant Pathologist in the Experiment Station, Riverside.

Publication Information

Hilgardia 21(12):331-366. DOI:10.3733/hilg.v21n12p331. April 1952.

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This paper is a report of an anatomical research undertaken in 1947 on the trunks of mature sweet orange trees on sweet orange rootstock. Object of the investigation was to determine the time at which new trunk phloem is produced, with respect to the time of shoot and root extension growth and xylem production. Also investigated were the anatomic features of xylem and phloem development; the portion of the phloem which is replaced during the year; and how and when the older sieve tubes degenerate.

Appended to the present report is a detailed method for collecting, sectioning, and staining large batches of citrus phloem.

Table of Contents is on outside back cover.

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Schneider H. 1952. The phloem of the sweet orange tree trunk and the seasonal production of xylem and phloem. Hilgardia 21(12):331-366. DOI:10.3733/hilg.v21n12p331
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