Urticaceae

  • Family

    Urticaceae (Magnoliophyta)

  • Scientific Name

    Urticaceae

  • Common Names

    Nettle Family

  • Description

    Number of genera: 45

    Number of species: 700

    Description (from PLANTAE): Herbs, sometimes shrubs or small, soft-wooded trees, the trees sometimes with buttresses, very rarely lianas. Sap clear, rarely white, frequently with mucilage cells and sometimes with non-articulated latex canals. Epidermis sometimes with urticating prickles (stinging), often with cystoliths, the cystoliths fusiform or punctiform. Indument sometimes urticating. Stipules usually present, lateral or intrapetiolar, often fused, often small. Monoecious or dioecious. Leaves alternate or opposite, often anisomorphic, simple, entire or 3-5(7) lobed; venation pinnate, the base often palmately 3-nerved, the cystoliths often visible on the abaxial surface of dried leaves. Inflorescences usually axillary, often paored, panicles, glomerules, or spikes. Flowers actinomorphic or zygomorphic, unisexual, small; perianth uniseriate; tepals 0-5; androecium of 3-5 stamens, the stamens antitepalous, inflexed in bud, elastically bending outward at anthesis; pistillodes often present; gynoecium syncarpous, the ovary superior, free from the perianth, the carpels 2, the locule 1, the stigma 1, comose or elongate; placentation basal, the ovule 1. Fruits achenes, small, sometimes partially enclosed in perianth, the perianth usually dry, sometimes fleshy (then fruits drupaceous). Seeds small.

    Taxonomic notes (from PLANTAE): The family is placed in the Urticales along with Ulmaceae, Moraceae, Cannabaceae and Cecropiaceae. The relationships among these families has long been recognized and is confirmed by more recent molecular evidence, although some studies place the group among the Rosales. The family is subdivided into five tribes based on the presence or absence of stinging hairs and floral characters.

    Distribution (from PLANTAE): Nearly cosmopolitan (Urtica), but most genera and species in tropical America and Asia, frequently in moist conditions at middle elevations and forest edges.

    Economic uses (from PLANTAE): The pollen is forciby ejected from the elastic stamens and carried on the small wind currents prevelant on the forest floor and near running water. Members of the tribe Urticeae produce stinging hairs or prickles. The compound generally responsible is formic acid, the same substance produced by many stinging ants. The cosmopolitan Urtica dioica is rendered harmless by immersion in hot water and is eaten throughout its range. The southeast Asian genus Dendrocnide, produces very painful rashes, wholly different from the pain caused by Urtica, Laportea and Urera. As the author knows from personal experience, contact with the plant is instantly painful, like a cross between a burn and a bee sting. As the pain subsides, the affected area reddens and eventually develops a scab. A permanent scar along with the painful memory is the end result. There are reports of human and animal mortality caused by the genus in Australia. In Mexico some species of Pouzolzia, Myriocarpa, Urera and Urtica are used to make amate paper. In the Old World, the flax-like fibers from Boehmeria (raime) are used to make cloth and paper. Egyptian mummies were wrapped in raime fibers from Boehmeria nivea. In Hans Christen Anderson's "the Swan", the princess condemed to weave coats of mail from nettles (Urtica) was saved by the nearly identical raime plant.

  • Floras and Monographs

    Urticaceae: [Book] Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.

    Urticaceae: [Book] Britton, Nathaniel L. & Millspaugh, Charles F. 1920. The Bahama Flora.