Slide 29: cross section of a woody stem in its second year of growth. The cork cambium has become active and produced the non-living cork cells on the outside of the stem. Underneath the periderm lies the phloem, the fibers of which are stained red. Inside the phloem lies the vascular cambium and internal to the cambium is the xylem. There is a small amount of pith in the center of the stem. Where would the primary phloem be located? ...the secondary phloem? ...the primary xylem? ...secondary xylem? Note the two annual rings showing that the stem is in its second year of growth. (Fig. 35.22, p. 754.)