Araucaria

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Plant Characteristics
Cultivation
Scientific Names

Araucaria >


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Read about Araucaria in the Standard Cyclopedia of Horticulture 

Araucaria (Chilean name). Including Columbea and Eutacta. Pinàceae. Large South American and Pacific Australian evergreen trees (about a dozen species), grown in their juvenile state in greenhouses and windows and often used in summer for lawn decoration; they are very decorative pot-plants.

Tall strict or widely branching conical trees: Lvs. small, scale-like and stiff, clothing all the branches uniformly and usually closely imbricated: fis. mostly dioecious, the staminate terminal and solitary or disposed in fascicles; anthers 6-8-celled; pistillate fls. in ovoid or globose heads that become large woody cones with only 1 seed underneath each scale.—The South American species (Columbea) have scarcely winged cone- scales, the cotyledons 2, and the germination hypogeal (cotyledons remaining below ground I; the Australian and Pacific species (Eutassa) have winged scales, cotyledons 4, and germination epigeal.

Araucarias are probably the most prized pot evergreens in cultivation. They are much used in house decoration, particularly at Christmas time, as they are not only attractive but will stand much hard usage. A. excelsa (Fig. 300) is the one commonly seen in residences. Propagation is by seeds and cuttings, as given under A. excelsa below. Symmetrical plants are secured from the leading shoots. Side shoots are likely to make misshapen specimens, as seen in Fig. 301. The araucarias need cool treatment. The temperature should not be above 60° at night. If kept too crowded or not given sufficient light, they become ragged and straggling, as in Fig. 302. In summer the plants should be protected from direct burning sun.

The species thrive in the open in southern Florida and in parts of California. A. imbrícata is the hardiest. It is rarely seen in greenhouses. A. Bidwillii is apparently the second hardiest, and also one of the best species for all purposes. A. excelsa and its allies are about as hardy in southern Florida as crotons and acalyphas.

The commonest species in greenhouses is A. excelsa. It is grown on an enormous scale in many nurseries for decoration as window or table plants. When raised from seed the plants grow rapidly and the branches are invariably disposed in tiers with wide internodes, often as much as 2 feet separating each tier of branches. Such plants are of little use for ordinary decorative work and recourse is made to plants raised from cuttings. This practice has grown up as it is found that plants raised from cuttings assume a dwarf compact habit, with the tiers of branches placed close together, and that they do not grow into large specimens until many years old. The plants for stock purposes are usually raised from seed, and when they nave formed some three to six tiers of branches the tops are taken out and put in as cuttings in light sandy compost in a close house or case at a temperature of about 60° F. They are kept shaded from hot sun and damped over frequently until rooted. The stock plants are kept growing and soon break out into new growth in the axils of each of the upper branches. These are all "leader" growths, and when long enough they each furnish a suitable cutting which is treated in the same way as the primary growth or leader. After each of these has been removed for stock, the stem of the stock plant is cut off to the next tier of branches, which in turn will furnish another set of cuttings and so on until the plant is reduced to the bottom layer of branches, when it is discarded and another stock obtained again from seed. It should be pointed out that the branches themselves may be rooted as cuttings, but they always retain their flat asymetrical shape and are useless for stock purposes. (See Fig. 301.)


The above text is from the Standard Cyclopedia of Horticulture. It may be out of date, but still contains valuable and interesting information which can be incorporated into the remainder of the article. Click on "Collapse" in the header to hide this text.


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Araucaria
Araucaria columnaris
Araucaria columnaris
Plant Info
Scientific classification
Kingdom: Plantae
Division: Pinophyta
Class: Pinopsida
Order: Pinales
Family: Araucariaceae
Genus: Araucaria
Juss.

Species
See text.

Araucaria is a genus of evergreen coniferous trees in the family Araucariaceae. There are 19 species in the genus, with a highly disjunct distribution in New Caledonia (where 13 species are endemic), Norfolk Island, eastern Australia, New Guinea, Argentina, Chile, and southern Brazil.

Many if not all current populations are relictual and restricted. They are found in forest and maquis shrubland, with an affinity for exposed sites. These columnar trees are living fossils, dating back to early in the Mesozoic age. Fossil records show that the genus also formerly occurred in the northern hemisphere until the end of the Cretaceous period.

Petrified cone of Araucaria sp. from the Jurassic (210 mya) of Patagonia, Argentina

The genus is familiar to many people as the genus of the distinctive Monkey-puzzle Araucaria araucana. The genus is named after the Arauco Indians of central Chile and south-west Argentina whose territory incorporates natural stands of this species, where it is known as the Pehuén. These Native Americans, who name themselves the Pehuenche ('people of the Pehuén'), harvest the seeds extensively for food. No distinct vernacular name exists for the genus; many are erroneously called 'pine', despite their being only very distantly related to pines (Pinus).

They are mainly large trees with a massive erect stem, reaching a height of 30-80 m. The horizontal, spreading branches grow in whorls and are covered with leathery or needle-like leaves. In some species, the leaves are narrow awl-shaped and lanceolate, barely overlapping each other, in others they are broad and flat, and overlap broadly.

The trees are mostly dioecious, with male and female cones found on separate trees, though occasional individuals are monoecious or change sex with time. The female cones, usually high on the top of the tree, are globose, and vary in size between species from 7-25 cm diameter. They contain 80-200 large, edible seeds, similar to pine nuts though larger. The male cones are smaller, 4-10 cm long, and narrow to broad cylindrical, 1.5-5 cm broad.

Classification and species list

There are two sections in the genus, sometimes treated as separate genera:

  • Section Araucaria. Leaves broad; cones more than 12cm diameter; seed germination hypogeal. Syn. sect. Columbea; sometimes subdivided into three sections or subsections.
    • Araucaria angustifolia. Paraná Pine (obsolete: Brazilian Pine, Candelabra Tree). Southeastern Brazil, northeastern Argentina.
    • Araucaria araucana. Monkey-puzzle or Pehuén (obsolete: Chile Pine). Central Chile & western Argentina.
    • Araucaria bidwillii. Bunya-bunya. Eastern Australia (sometimes placed in sect. Bunya).
    • Araucaria hunsteinii. Klinki. New Guinea (sometimes placed in sect. Intermedia).
  • Section Eutacta. Leaves narrow, awl-like; cones less than 12cm diameter; seed germination epigeal.

See the Royal Botanic Gardens Edinburgh web site for New Caledonian Araucaria research http://www.rbge.org.uk/rbge/web/science/research/biodiversity/arauc.jsp

Uses

Some of the species are relatively common in cultivation because of their distinctive, formal symmetrical growth habit. Several species are economically important for timber production and the edible seeds.

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External links

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