The prothallus can only survive if water is continuously available and fertilization requires water for the sperm to swim to the archegonia. The result of fertilization is a zygote which grows out of the prothallus into the new sporophyte. Whole prothallus with rhizoids Antheridium and archegonia Fern propagation from spores is a rather uncertain process, although some ferns seem to be able to spread all over a greenhouse without too much trouble. Much of the time ferns reproduce vegetatively. Although living ferns are mostly herbaceous, terrestrial plants there are tree-like plants, aquatics and epiphytes.
Most species are tropical, although ferns are a component of all but the driest ecosystems on earth.
For us they are mainly ornamental plants both in the landscape and as indoor plants. The bracken fern, Pteridium aquilinum is one of the most troublesome weeds of pasture in Northern latitudes. All rights reserved.