Cambial meristematic cells

YM. et al (2010) Cultured cambial meristematic cells as a source of plant natural products. Nat Biotechnol, 28, 1213-1217,... 

Wood Cell Production. The site of wood cell production, the vascular cambium, is illustrated in Figure 3B. Technically, it is a microscopic sheath of meristematic cells. However, the exact circumferential line of cambial cells is very difficult to locate precisely, particularly during the tree s growing season, because of the presence of recent xylem and phloem derivatives. Therefore, it is more common to reference this lateral meristem as the cambial zone (2). 

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