Cork is a tissue found in some plants, which consists tightly packed dead cells. It allows improved insulation and prevents loss of water or nutrients on the inner bark of wooded plants. This tissue is often extracted from Cork oak and manufactured into various products (see cork (material)). Biological tissue is a substance made up of cells that perform a similar function. ... For other meanings of bark, see Bark (disambiguation). ... A woody plant is any vascular plant that has a perennial woody stem -- that is, one that supports continued vegetative growth above ground from year to year. ... 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. ...