In vascular plants, secondary growth or, perhaps more accurately, secondary thickening is the result of the activity of the vascular cambium. The latter is a meristem that divides off cells: the cells on the inside of the meristem (the adaxial side) will become secondary xylem, while the cells on the inside (the abaxial side) will become the secondary phloem. This growth increases the girth of the plant, rather than its length, hence the phrase "secondary thickening". As long as the vascular cambium continues to produce new cells, the plant will continue to grow more stout. If this is kept up over many years, this process produces wood. Divisions Non-seed-bearing plants Equisetophyta Lycopodiophyta Psilotophyta Pteridophyta Superdivision Spermatophyta Pinophyta Cycadophyta Ginkgophyta Gnetophyta Magnoliophyta The vascular plants are those plants that have specialized cells for conducting water and sap within their tissues, including the flowering plants, conifers and other gymnosperms, but not mosses, algae, and the like (nonvascular... Vascular cambium is a tissue found in the stems of perennial dicots. ... Meristem is a type of embryonic tissue in plants consisting of unspecialized, youthful cells called meristematic cells and found in areas of the plant where growth is or will take place - the roots and shoots. ... Plant cell structure Plant cells are quite different from the cells of the other eukaryotic kingdoms organisms. ... Secondary xylem is formed by a vascular cambium. ... A tree trunk as found at the Veluwe, The Netherlands Wood derives from woody plants, notably trees but also shrubs. ...

Because this growth ruptures the epidermis of the stem, woody plants also may have a cork cambium that develops among the phloem. The cork cambium gives rise to thickened cork cells to protect the surface of the plant and reduce water loss. If this is kept up over many years, this process may produce a layer of cork. In the case of the cork oak it will yield harvestable cork. The epidermis is the outer multi-layered group of cells covering the leaf and young tissues of a plant. ... Cork cambium is a tissue found in woody plants as part of the periderm. ... Cork is a tissue found in some plants, which consists tightly packed dead cells. ... Binomial name Quercus suber L. The Cork Oak (Quercus suber) is a medium sized, evergreen oak tree in the section Quercus sect. ... A cork stopper for a wine bottle A Champagne cork Cork material is a subset of generic cork tissue, harvested for commercial use primarily from the Cork Oak tree, Quercus suber, with Portugal producing most cork worldwide. ...