Nootka cypress

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Nootka cypress
Leaves and immature cones of the Nootka false cypress (Xanthocyparis nootkatensis)

Leaves and immature cones of the Nootka false cypress ( Xanthocyparis nootkatensis )

Systematics
Class : Coniferopsida
Order : Conifers (Coniferales)
Family : Cypress family (Cupressaceae)
Subfamily : Cupressoideae
Genre : Xanthocyparis
Type : Nootka cypress
Scientific name
Xanthocyparis nootkatensis
( D.Don ) Farjon & DKHarder

The Nootka false cypress or Nutka false cypress ( Xanthocyparis nootkatensis ), also known as Alaska cedar , is a conifer of the cypress family (Cupressaceae) that is native to North America and is widely planted as an ornamental tree . Often it can be found under the older name Chamaecyparis nootkatensis (D.Don) Spach . The species was discovered in 1793 by the biologist Archibald Menzies on Nootka Sound near Vancouver Island . This is where its German and scientific name comes from.

description

Habitus

The Nootka false cypress is between 23 and 38 meters high and reaches breast height diameters of 60 to 100 centimeters. The trunk base of the straight trunk is somewhat widened, but does not have any noticeable roots. The narrow crown is loosely branched and therefore appears transparent. The trunks and branches of young trees are extremely flexible. Under unfavorable conditions, the Nootka false cypress also grows shrub-like.

Foliage

The clearly pointed, scaly leaves are green, yellow-green, and rarely blue-green in color. They are about 3 millimeters in size, but can also become significantly longer on fast-growing branches. The upper third of the angular leaves spread out from the shoot. A distinction is made between a youth and an age form for the leaves. The pointed and needle-shaped leaves of the juvenile form occur on trees up to the age of 4 years. The leaves of the age form then have the typical scale-like shape. The leaves give off a pungent odor when rubbed.

Flowers, cones and seeds

Male cones
Seeds

The Nootka false cypress is single-sexed ( monoecious ). The flowering time varies between April and June, depending on the location. The elongated, pale yellow male cones are around 4 millimeters in size, as are the spherical, green to slightly reddish colored female cones. Both the female and male cones sit on the ends of young shoots. The cones ripen for two years, only one year in the south. Therefore, both ripe and immature cones can be found on the branches . The young and still soft cones are green with red stripes. The harder ripe cones are spotted yellow-green and brown. After opening and the discharge of seeds in autumn or early summer, they are brown to gray in color. The flattened reddish brown seeds are 3 to 5 millimeters long. They have two opposite small wings. The thousand grain weight is around 4 grams.

bark

bark
Nootka false cypress trees in the Gotha Castle Park

The Nootka false cypress has a relatively thin bark . The bark of the young trees is smooth and reddish brown in color. The bark of the old trees takes on a silvery color and comes off in thin longitudinal strips. This makes it appear furrowed. Some old trees keep the bark of the young plants into old age. The bast contains easily recognizable resin channels.

root

The species forms a very shallow root system . It forms mycorrhizae . However, there is still no information about which fungi it dies with. The Nootka false cypress can spread via root brood .

Wood

The light yellow heartwood is surrounded by a narrow white sapwood and does not contain any resin channels. The heartwood is extremely resistant to rot and smells pleasantly aromatic. Because of its slow growth, it has a very even structure and there are hardly any differences in density between early and late wood. The substances channelsotin , nootkatin , chamic acid and chaminic acid were isolated from the heartwood , which contribute to rot resistance, wood color and odor. The kiln density is approx. 0.46 g / cm³, the bulk density with a wood moisture content of 12 to 15% is approx. 0.55 g / cm³.

Physical Properties value unit
Flexural strength 900 kg / cm²
Compressive strength parallel to the fiber 460 kg / cm²
Tensile strength perpendicular to the fiber 35 kg / cm²
Shear strength parallel to the fiber 95 kg / cm²

Distribution and location

The natural range of the Nootka cypress extends on the Pacific coast of North America from the Siskiyou Mountains in northern California to Port Wells on Prince William Sound in Alaska . The distribution area only extends around 160 kilometers inland. The Nootka false cypress is a tree species from the cool, humid climate. The species is found at altitudes from 0 to 1,200 m. ü. NN. It tolerates nutrient-poor soils as long as there is enough moisture. It is a shade tree species and mostly forms pure stands. They can be found on the edges of meadows, rivers and lakes, in moors, on steep, shallow slopes, in avalanches, on seepage surfaces and on rocky ridges.

Diseases and pests

The Nootka false cypress is only seriously threatened by a few pests. Bark beetles of the genus Phloeosinus cause already weakened trees to die. The fungus Gymnosporangium nootkatense attacks leaves and twigs, but does not cause any major damage. Fungi of the genus Apostrasseria lead to shoot deaths in seedlings and thereby cause considerable damage. Old trees are very often attacked by trunk rot, which, however, only leads to trunk breaks. Seedlings are bitten by deer . Brown bears cause trunk injuries that serve as a target for harmful fungi. The biggest problem is the so-called Yellow Cedar Decline , which occurs on more than 200,000 hectares on the Alaskan coast. It leads to the death of the trees, although the cause is not yet known.

use

The wood is considered to be one of the most valuable in North America. It is used in house construction, in cabinet making and in furniture construction. Poor quality wood is used to make fence posts, seats, and ship decks. Because of its pleasant aroma, it is also a popular firewood. The Indians made canoe paddles, totem poles and household appliances from the wood of the Nootka false cypress. Houses used to be covered with bark and mats and blankets were woven.

Systematics

The Nootka false cypress has long been part of the genus Chamaecyparis . The affiliation of the species to this genus or to Cupressus has been discussed many times. With the discovery of a new species in Vietnam, the genus Xanthocyparis was established and the Nootka false cypress was transferred to this new genus. Molecular genetic studies confirmed the close relationship between the two species. For the discussion about the correct name of the genus see there .

The Leyland cypress ( Cupressus × leylandii ) is a hybrid that emerged from an unintended crossing of the Nootka false cypress with the Monterey cypress ( Cupressus macrocarpa ). Hybrids of the Nootka false cypress with Cupressus arizonica var. Glabra and the Mexican cypress ( Cupressus lusitanica ) are also described.

swell

  • Schütt, Weisgerber, Schuck, Lang, Stimm, Roloff: Lexicon of Conifers . Nikol, Hamburg 2008, ISBN 3-933203-80-5 , p. 125-133 .

Individual evidence

  1. ↑ Miroslav M. Grandtner: Elsevier's Dictionary of Trees: Volume 1: North America . Verlag Elsevier , 2005, ISBN 0-444-51784-7 , p. 192
  2. ↑ Rudi Wagenführ: wooden atlas . 6th, revised and expanded edition, Munich 2007, ISBN 3-446-40649-2 , p. 178
  3. ^ A. Farjon, Nguyen Tien Hiep, DK Harder, Phan Ke Loc, L. Averyanov: A New Genus and Species in Cupressaceae (Coniferales) from Northern Vietnam, Xanthocyparis vietnamensis . Novon, Vol. 12, 2002, pp. 179-189.
  4. ↑ Damon P. Little, Andrea E. Schwarzbach, Robert P. Adams, Chang-Fu Hsieh: The circumscription and phylogenetic relationships of Callitropsis and the newly described genus Xanthocyparis (Cupressaceae). American Journal of Botany, Volume 91, 2004, pp. 1872-1881. (On-line)

Web links

Commons : Nootka False Cypress  - Album with pictures, videos and audio files