Cyatheales

Tree fern with fronds before and after deployment

The tree ferns ( Cyatheales ) are an order of ferns.

Not all species within this order form distinct tribes. In addition, amenities not all tree-like ferns that order. In addition to the ferns in this order are found in the families Königsfarngewächse ( Osmundaceae ) and Rippenfarngewächse ( Blechnaceae ) some fern species with strains in the genera Blechnum, Leptopteris, Sadleria and Todea.

The tree ferns colonize the earth since the Jurassic.

Description

The order has no stand-out features common.

Some species have a stem -like growth habit, others have a creeping rhizome. Some have hairy stem axis, other scales. The sori abaxial sit ( on the underside of leaves ) or marginal ( on the leaf margin ). They are covered by an indusium or not.

The fronds of tree ferns are in full-grown specimens often about 1 meter long, and almost always feathered one or more times. However, a simple way has ungefiederte fronds.

Unlike seed plants, tree ferns show no growth in thickness of the trunk. The log is supported by the root bundles that form during growth.

The prothallus is green and heart-shaped.

Occurrence

Tree ferns grow in tropical and subtropical areas of the world. Some species tolerate the moderate climate of rainforests in Australia, Tasmania and New Zealand and adjacent regions (Malaysia, Lord Howe Island ). In general, tree ferns tolerate no ongoing drought, and only a few species (eg Dicksonia antarctica) survive mild frosts.

In studies in hitherto uninvestigated areas of New Guinea New species are regularly discovered. At the same time, some species are due to the collection for the ornamental trade, intensive logging and habitat loss greatly threatened or extinct.

Economic Importance

Tree ferns have been imported since the 19th century as ornamental plants to England and there about popular plants in the tropics worldwide. In many other areas of the world with only minor frosts, for example, in southern England with his ( influenced by the Gulf Stream ) maritime climate, the landscape planting in parks and gardens is possible.

Ornamental plants of commercial significance are found in the genera Cyathea and Dicksonia. In very bright, in winter cool rooms, or in conservatories some tree fern species can be maintained.

On the trunk and the fronds of older plants are long silky hair which have been used in China for treatment of bleeding and Hawaii as pillow stuffing.

System

The order Cyatheales is in all likelihood a monophyletic group. It is to Smith et al. (2006) divided into eight families:

• Family Thyrsopteridaceae Thyrsopteris Kunze, with only one type: Thyrsopteris elegans Kunze, an endemic tree fern from the Juan Fernandez Islands.

• Loxsoma R. Br ex A. Cunn, with only one species that grows in New Zealand.: Loxsoma cunninghamii R.Br.

• Culcita C. Presl, with only two species.

• Plagiogyria ( Kunze ) Mett. , With about 12-37 species in East Asia and the Americas

• Cibotium Kaulf. , With about 7-12 species in tropical Asia, Polynesia and America

• Alsophila R. Br (incl. Nephelea ), with at least 63 species
• Cyathea Sm, with at least about 300 species (including Cnemidaria, Hemitelia, Trichipteris )
• Gymnosphaera flower, with about 21 species
• Hymenophyllopsis Goebel, with seven species in northern South America
• Sphaeropteris Bernh. (including Fourniera ), with at least 13 species

• Calochlaena ( Maxon ) M.D. Turner & R. A. White, with five species.
• Dicksonia L' Herit., With about 7-25 species
• Lophosoria C.Presl, with only one type of tropical America: Lophosoria quadripinnata ( J. F. Gmel. ) C. Chr

• Metaxya C. Presl, with only one type in tropical South America: Metaxya rostrata ( Kunth ) C. Presl.

Pictures

Tree fern

Tree fern ( Dicksonia antarctica) in Nunniong, Australia

Cibotium glaucum ( Hapu'u pulu ) Hawaii

Tree ferns in Blendys Garden, Madeira

( Cyathea spinulosa ) tree ferns in the rainforest of Taiwan

Habitat

Tree fern in Malaysia

Tree fern in Madeira

Sori on a Fern