Secondary Growth


Pine stem cross-section showing xylem and phloem

Pine phloem with crushed old phloem

Pine: longitudinal section through cambium

Pine: tangential longitudinal section of secondary xylem

Pinus strobus: xylem cross-section.

Pinus strobus: xylem tangential-longitudinal section

Pinus strobus: radial-longitudinal section.  Note pits in ray tracheid at the top of the ray crossing this image.

Drimys (vesselless angiosperm) in transverse section through xylem.

Drimys secondary xylem ray in transverse section of a stem

Drimys stem in radial-longitudinal section showing ray cells.

Drimys xylem in tangential-longitudinal section

Closer view of Drimys stem xylem showing tapered, non-perforated tracheid ending.

Drimys tracheid pitting

Drimys tracheid pitting

Tilia stem transverse section

Tilia secondary phloem

Tilia phloem close view

Tilia phloem in radial-longitudinal section.  Note alternating bands of fibers and sieve tube members.

Tilia periderm in radial-longitudinal section

Wide view of Quercus alba xylem transverse section showing very wide earlywood vessels

Latewood portion of Quercus alba xylem growth ring

Transverse xylem section from Quercus alba showing wide and narrow rays.

Transverse xylem section from Quercus alba showing thick-walled fibers

Quercus alba xylem in tangential-logitudinal section showing a wide ray

Quercus alba xylem in radial-logitudinal section showing a wide vessel

Quercus alba xylem in radial-logitudinal section showing fibers

Quercus alba xylem in radial-logitudinal section showing short parenchyma cells

Juglans xylem transverse section.

Juglans (black walnut) xylem tangential-longitudinal section

Juglans (black walnut) xylem radial-longitudinal section showing tyloses in wide vessel

Juglans (black walnut) xylem radial-longitudinal section showing simple perforation plates in wide vessels

Young Sambucus stem

Sambucus xylem growth ring. From left: pith, primary xylem, secondary xylem, cambium, secondary phloem

Sambucus xylem in transverse section

Sambucus cambial region.  Note crystals in phloem cells

Young Liriodendron stem

Liriodendron secondary xylem

Liriodendron stem showing ray dilatation in the phloem