North American Fruit Explorers mailing list at ibiblio

[Jwlehman@aol.com]

Dear Heron,

I'm going to let my ignorance hang out here and hopefully I'm not the only reader with this question.

Correct me here if I'm wrong. The vascular cambium lies between the xylem (inside) and phloem (outside). Cambium cells divide in three directions with the inside cells becoming xylem and the outside cells becoming phloem. The third direction is sideways allowing the cambium ring to expand and push out as xzlem is formed inside pushing this cambium ring out. Outside of the phloem is a cork cambium which grows cork which becomes bark. 

My question is likely because there is a fine point in the above I'm missing. What becomes of the phloem ring as the vascular cambium ring grows outward. Where do they go or stated in another way, what happens to those phloem cells? Are the phloem cells incorporated into the cambium? Are they pushed outward and convert to cord cambium?    

Just trying to learn more.

Jerry Lehman