Nettle

Nettle is a perennial herbaceous plant. It forms underground, branched, yellowish rhizomes, from which the vegetative stems are formed, erect and leafy, with a square section, which rise during the good season up to a height of 2 m. The leaves, pedunculated and opposite, are heart-shaped to rhomboidal with a clearly serrated margin. The flowers, tetramers, are small, yellow-greenish, collected in spikes in the axils of the leaves in the upper part of the stem. The male and female flowers are borne in different, dimorphic spikes. A salient feature of the plant is the epidermis of the entire epigeal part which is covered with stinging bristles. These are made up of unicellular hairs with a silicified and extremely fragile wall, which easily penetrate the skin, releasing the cellular contents onto the lesion. The high content of histamine and acetylcholine causes irritation. Nettle is a nitrogen-hungry plant and grows on fresh, fertile soil. It thrives wherever there is an abundance of nutrient-rich litter, preferring moist locations. It is thus found in the ruins of old manure heaps, along sewage canals, on the edge of lush woods. It is common throughout Italy.