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These spores are produced in sporangia that develop on the leaves of the fern's sporophyte. The fern can also reproduce by the division of its rhizomes. On the underside of the blades, the sori (reproductive clusters) are round, discrete, and sunken. Their outline can be seen as raised dimples on the upper surface.
As one of the oldest plant groups on Earth, these hardy greens can survive just about anything—as long as their environment doesn't get too dry. They can even help keep soil intact during ...
An annulus in botany is for ferns an arc or a ring of specialized cells on the sporangium. These cells are arranged in a single row, and are associated with the release or dispersal of spores. In mosses it is a ring of cells around the tip of the sporangium. In flowers it is a ring of hairs within the flower tube.
Its leaves are scale-like and appressed, like a mature cedar, and it is glossy and evergreen. It normally grows to a height of about four inches (10 cm), with the spore-bearing strobili held higher. This plant was once widely harvested and sold as Christmas greenery, and populations were widely depleted for this reason.
Polypodium glycyrrhiza, commonly known as licorice fern, many-footed fern, and sweet root, is a summer deciduous fern native to northwestern North America, where it is found in shaded, damp locations. Spores are located in rounded sori on the undersides of the fronds, and are released in cool weather and high humidity. [1]
Polypodiales are unique in bearing sporangia with a vertical annulus interrupted by the stalk and stomium. [2] These sporangial characters were used by Johann Jakob Bernhardi to define a group of ferns he called the "Cathetogyratae"; [3] the Pteridophyte Phylogeny Group has suggested reviving this name as the informal term cathetogyrates, to replace the ambiguously circumscribed term "polypods ...
Dryopteris marginalis showing unripe sori placement on the edges of the leaves. Dryopteris marginalis is an evergreen fern throughout its range, along with Christmas fern (Polystichum acrostichoides) it is one of the few evergreen ferns. Marginal wood fern grows from a clump with a prominent central rootstock, this rootstock may be exposed and ...
The sori, producing the spores, are large and round. Like many tree ferns, it features a "skirt" of dead leaves that do not drop off the crown and form a barrier for parasitic climbing plants. Like many tree ferns, it features a "skirt" of dead leaves that do not drop off the crown and form a barrier for parasitic climbing plants.