Aðalbarka

Aðalbarka is an Icelandic term that translates to "main bark" or "primary bark." In botanical contexts, it refers to the outermost layer of a woody plant's stem or root. This layer is crucial for the plant's survival and protection. The aðalbarka typically consists of several distinct tissues. The outermost part is the periderm, which is a protective covering that replaces the epidermis as the stem or root grows thicker. The periderm includes the cork (or phellem), cork cambium (or phellogen), and cork parenchyma (or phelloderm). Beneath the periderm lies the phloem, responsible for transporting sugars produced during photosynthesis from the leaves to other parts of the plant.

The aðalbarka plays a vital role in protecting the plant from mechanical injury, desiccation, and pathogen invasion. It also helps regulate gas exchange through lenticels, which are small pores in the bark. The thickness and texture of the aðalbarka can vary significantly between species, influenced by factors such as age, environmental conditions, and the plant's growth habit. In some species, the bark may be smooth, while in others, it can be rough, fissured, or even peeling. The study of bark characteristics is often used in dendrology and forestry for species identification and assessment of tree health.