2780 x 3812 px | 23,5 x 32,3 cm | 9,3 x 12,7 inches | 300dpi
Aufnahmedatum:
13. Februar 2012
Weitere Informationen:
Dryopteris marginalis is known as the marginal shield fern or marginal wood fern. The marginal wood fern favors damp shady areas and is found throughout eastern North America. It favors moderately acid to circumneutral soils. It favors cooler areas, but is fairly drought-resistant once established. In the warmer parts of its range, it is most likely to be found on north-facing non-calcareous rock faces.The evergreen leaves reach a maximum length of 1 - 2 ft, with a single crown on each rootstock. The round sori are located on the margins of the leaf tissue, hence the common name. Just before the spore ripens, the sori turn an interesting blue-violet color. A fern is any one of a group of about 12, 000 species of plants belonging to the botanical group known as Pteridophyta. Unlike mosses, they have xylem and phloem (making them vascular plants). They have stems, leaves, and roots like other vascular plants. Ferns reproduce via spores and have neither seeds nor flowers. By far the largest group of ferns is the leptosporangiate ferns, but ferns as defined here (also called monilophytes) include horsetails, whisk ferns, marattioid ferns, and ophioglossoid ferns. The term pteridophyte also refers to ferns and a few other seedless vascular plants (see classification section below). Ferns first appear in the fossil record 360 million years ago in the Carboniferous but many of the current families and species did not appear until roughly 145 million years ago in the early Cretaceous (after flowering plants came to dominate many environments). Ferns are not of major economic importance, but some are grown or gathered for food, as ornamental plants, for remediating contaminated soils, and have been the subject of research for their ability to remove some chemical pollutants from the air. Some are significant weeds. They also play a role in mythology, medicine, and art.