Printer Friendly

Araucaria.

"The bulk of the forest mass was conspicuous from far away because of the huge size of the trees, which are distinguished by their upper silhouette, of horizontal and parallel lines, as if they were cedars... The interior, though the crowns are touching, is less dense than might be expected. The tallest trees rise 20-30 m before they produce first branches, and they may be up to 2 m in diameter. This large size and the lack of lower branches seem to be a problem for lianas, whose absence is noteworthy. From outside, the edges of the forest, stretch further to the north and to the south than the eye can see."

This is the way the Swedish botanist Carl Axel Magnus Lindman (1856-1928) described the forests of Araucaria in Brazil in the late nineteenth century. Lindman's botanical explorations of Rio Grande do Sul (1892-94), performed with funds left by the Swedish-Brazilian naturalist and patron A.F. Regnell to the Academia Imperial de Ciencias of Brazil, were published in Swedish, in Stockholm (in 1900), and are a classic study of the vegetation of South America. He points out the great importance of the Araucaria trees in the local economy, and of their relevance in the landscape. Araucaria trees are not just any trees.

The species of Araucaria that occurs in Brazil, the Parana pine (Araucaria angustifolia), is locally known as the pinho or pinheiro de Parana. The name of the capital of Parana Province, Curitaba, is derived from two terms in Guarani, kuri'y, the tree's name in Guarani, and tyba, meaning a group. On the western side of South America, in the Chilean-Patagonian Andes, the local name of the monkey-puzzle tree (A. araucana) is pehuen, a reference to the Pehuenche, a branch of the Mapuche, or Araucanian, Indians who have lived in the area since time immemorial. Thus, the name of a major city is a permanent reminder of the great landscape and ethnobotanical significance of these unusual trees.

Araucaria spp. are a relict of the past, like most of the gymnosperms, the group to which pines, firs and cypresses all belong. During the Tertiary, forests of Araucaria covered much of the planet. Fossil remains have even been found in Greenland, including remains of some surviving species. Only about a dozen species of Arau-caria still survive, the two South American species already mentioned, and a few more that hang on in a few scattered patches in Australia and the islands of Oceania, such as the Norfolk Island pine (Araucaria heterophylla [=A. excelsa]), which is widely cultivated in gardens in southern Europe as an ornamental, the hoop pine, or Moreton Bay pine (A. cunninghamii), from New South Wales, and the bunya-bunya, or bunya pine (A. bidwillii) from Queensland. They are the impressive last remains of a splendid past, as are the kauri pines (Agathis spp.), the only other surviving genera of the Araucariaceae, and restricted to islands in the Pacific Ocean. In New Zealand, the kauri pine (A. australis) is one of the most important native trees, and in the temperate and tropical rainforests in Australia, there are a further three species of Agathis, the most important of which is A. robusta, found in the temperate rainforests of southern Queensland and northeast New South Wales.

The Araucaria are a magnificent rarity. For this reason, they are cultivated in many gardens in the temperate zones, where they can survive despite their lack of success in the wild. They are strikingly ornamental. They are large trees, 164 ft (50 m) tall or more, with an unmistakable pattern of branching. The branches are arranged in regular whorls on the straight main stem. In old specimens, which may be several centuries old, only the tip of the main trunk bears branches, making old trees look rather like an enormous parasol, with the crown reduced to the ribbing of an enormous parasol. This is why the silhouette of the Brazilian forests is so unmistakable, as Lindman pointed out.

That is not all. Araucaria trees have very unusual leaves, tough green scales arranged spirally (showing the primitive nature of the group) and regularly around the branches, which they completely cover. The female specimens (usually dioecious, with separate male and female plants) produce remarkably large cones, the size of a melon. These cones consist of numerous seed-bearing scales (150 or more), which are also arranged spirally, bearing large seeds, the size of an almond. These pine nuts are highly nutritious, and are of great importance for many small mammals, reptiles, and birds, including the attractive blue jay (Cyanocorax caeruleus) of the tropical rainforests of Brazil. The fact that the native peoples eat these nuts, and sell them in all the markets in the area, clearly shows how important a foodstuff this Araucaria is in the environments where it grows, usually sites with unproductive soils.

Araucaria trees do not require very good soils, and some specimens of A. angustifolia can grow more than 16 ft (5 m) in height within 13-14 years. At this stage, their growth is more or less pyramidal, like the firs, as they do not start to look like a parasol until they are more than 100 years old. The wood of Araucaria is highly valued, especially the old (300-500 years) trunks, as they are straight, thick, and long. This is why they are now endangered, as their natural area of distribution, in the tropical mountains in Brazil (23-30[degrees]S), is constantly declining.
COPYRIGHT 2000 COPYRIGHT 2009 Enciclopedia Catalana, SAU
No portion of this article can be reproduced without the express written permission from the copyright holder.
Copyright 2000 Gale, Cengage Learning. All rights reserved.

Article Details
Printer friendly Cite/link Email Feedback
Publication:Encyclopedia of the Biosphere
Geographic Code:1USA
Date:Jun 1, 2000
Words:909
Previous Article:The temperate and subtropical evergreen broadleaf forests and similar forests.
Next Article:Camellias and magnolias.
Topics:

Terms of use | Privacy policy | Copyright © 2020 Farlex, Inc. | Feedback | For webmasters