What is Ginkgo? View in a new way! Što je to ginko? Prikaz na novi način!

srijeda, 22. travnja 2009.

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Rezime na eng. jeziku:

"Chamaecyparis Spach 1841

Common names

Cypress (Rushforth 1987, Welch and Haddow 1993), white-cedar, false-cypress, faux-cypres (Michener 1993).

Taxonomic notes

Five species depending on taxonomic opinion. Some authors include all species of Chamaecyparis in the genus Cupressus (Michener 1993), but genetic studies indicate they are generally not particularly closely related (Brunsfeld et al. 1994, Gadek and Quinn 1993). One species sometimes included in this genus, Ch. funebris, is here assigned to Cupressus, and another, Ch. nootkatensis, is here assigned to Xanthocyparis (Rushforth 1987, Welch 1991, Farjon 1998, Gadek et al. 2000) on the basis of various lines of evidence. Two other taxa sometimes treated as species (Ch. henryae and Ch. taiwanensis) are usually treated as subspecies or varieties of Ch. thyoides and Ch. obtusa respectively. Cultivated juvenile forms of several species have been referred to the superfluous Retinospora Siebold & Zuccarini.

Description

Tall monoecious trees (rarely shrubs) of pyramidal habit, the bark smooth, peeling off in strips or scales or fissured into ridges. Leading shoots nodding, branches spreading, the branchlets dorsiventrally flattened, rarely (Ch. thyoides) more or less terete or rhombic in cross section, in fan-shaped or pinnately flattened sprays. Leaves opposite in 4 ranks. Juvenile leaves subulate. Mature leaves opposite, scale-like, lateral and facial pairs of differing shape, similar in size or the facial pairs smaller, and closely overlapping, ovate to rhombic, acuminate to obtuse, entire. Staminate cones ovoid to oblong, yellow or (usually) red, stamens decussate, with 2-3 pairs of sporophylls, each sporophyll with 2-4 pollen sacs. Ovulate cones maturing and opening in 6-8 months from pollination, shed soon after seed release, globose to ovoid-globose, green or violet, often glaucous, maturing brown, 4-12(-14) mm; scales persistent, (2-)3-5(-6) pairs, peltate or basifixed, thick and woody, the terminal pair fused. Seeds (1)2-4(5) per scale, slightly compressed, with 2 equal, membranaceous wings. Cotyledons 2, rarely 3. x = 11 (Li 1975, Michener 1993, Walker 1976).

Range

North America, Japan and Taiwan (Li 1975).

Big tree

See Ch. formosensis.

Oldest

I have no reliable age data for any of the species. Based on life history, distribution, and analogy with similar members of the Cupressaceae, it seems likely that the oldest trees are more than 1,000 years old.

Dendrochronology

Ethnobotany

The genus is of immense importance to modern horticulture; two species (Ch. lawsoniana, Ch. pisifera) account for perhaps 80-90% of the ornamental conifers grown in British gardens.

Observations

See the various species.

Remarks

The name Chamaecyparis is derived from the Greek: chamai = on the ground, and kyparissos = cypress (Walker 1976).
Several of the species show high variation in seedbeds, leading to the selection for horticultural use of many hundred cultivars. "Three [Ch. lawsoniana, Ch. pisifera, Ch. obtusa] are very variable and have given rise to a ridiculous flood of selected seedlings and mutations, many of which are so similar to others as to be just not worth perpetuating. Unfortunately this flow still continues. Very great restraint should now be exercised in introducing fresh forms that will add more names to our listings but no more beauty to our gardens" (Welch and Haddow 1993). This exasperated remark is followed by a 57 page list of Chamaecyparis cultivar names, including 29 pages with 559 names in Ch. lawsoniana alone - no wonder!

Citations

American Lumberman. 1911.11.11. "The Realization of a Great Commercial Dream." American Lumberman n.v. (November 11, 1911):43-142.
Welch, H.J. 1991. The Conifer Manual vol. 1.
Welch, H.J. and G. Haddow 1993. The World Checklist of Conifers.
This page co-edited with M.P. Frankis, 1999.02.

See also

Farjon (2005)." (Izvor: http://www.conifers.org/cu/ch/index.htm)


Rezime na eng. jeziku:


"Thuja
Linnaeus 1753

Common names

Arborvitae, thuya, cédre (Chambers 1993), ya bai shu (Chinese; Fu et al. 1999).

Taxonomic notes

Description

Evergreen, monoecious trees or shrubs. Branchlets in fan-shaped, flattened sprays. Leaves 4-ranked, scalelike, base decurrent only on leading branchlets, dimorphic along branchlets: facial pairs obovate-rhombic; lateral pairs boat-shaped, ridged abaxially, less than 4 mm, overlapping facial pairs, without conspicuous, white stomatal bands abaxially. Pollen cones with (4-)6-10(-16) microsporophylls, each with 2-4 pollen sacs. Seed cones maturing and opening first year, terminal, solitary, cone scales in 4-6 pairs, decussate, flat, only middle, larger 2 or 3 pairs fertile, each fertile scale bearing 1 or 2 seeds; free bract apex a very short mucro. Seeds 1-3 per scale, lenticular, with 2 lateral, narrow wings. Cotyledons 2 x = 11" (Chambers 1993, Fu et al. 1999). The following key is provided by Fu et al. (1999):
1a.
Leaves obtuse at apex, rarely subacute.

2a.
Facial leaves without a gland; young branchlets not glaucous
T. sutchuenensis
2b.
Facial leaves with a gland; young branchlets ± glaucous
T. koraiensis
1b.
Leaves subacute to acuminate at apex.

3a.
Leaves acuminate at apex; lateral leaves longer than facial leaves, apex straight
T. plicata
3b.
Leaves acute or subabcute at apex, lateral leaves slightly shorter than or as long as facial leaves, apex incurved.

4a.
Facial leaves with a conspicuous abaxial gland
T. occidentalis
4b.
Facial leaves without a gland
T. standishii

Range

North America, E Asia (Chambers 1993).

Big tree

Western redcedar, Thuja plicata, is far larger than the other species.

Oldest

Few or no data exist for the three Asian species, but Thuja plicata is clearly the oldest of the two North American species.

Dendrochronology

Considerable work has been done with Thuja plicata and Thuja occidentalis, and Thuja standishii has been investigated as well. See the species accounts for details.

Ethnobotany

The common name arborvitae is Latin for "tree of life" (17th cent.) because resins of these trees were used medicinally in western Europe. Effects include increasing blood pressure and reducing fever. The wood is reddish, light, and durable. Some of the larger species are valuable timber trees. The smaller species are cultivated in gardens and as wind screens for more tender plants.
Thuja plicata is extraordinarily significant to native peoples in its home range. The other species are less so.

Observations

See the species accounts.

Remarks

'Thuya'; was a Greek name for some evergreen, resinous trees (Chambers 1993).

Citations

See also

NA STRANICI http://www.conifers.org nalazi se mnogo podataka o pačempresima i tujama.

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