Talk:Polylepis

Latest comment: 12 years ago by Gkw11 in topic Class assignment

"Natural treeline" edit

I disagree completely that the "natural treeline" is 3200-3500 m in the Andes! Nonsense. How can you have native trees growing far above treeline?? At 3500 m in the Peruvian Andes the temperature rarely falls below freezing. That's not treeline. Consider that the snowline is roughly 5000 m. That would be 1500 m between treeline and snowline, which you simply don't see in nature. The treeline is far higher, at 4600 m -- the upper range of the Polylepis. Above that you may see juniper-like shrubs up to nearly 4900 m, but these probably don't qualify as "trees." --Rick DeLong (talk) 13:08, 16 January 2009 (UTC)Reply

Class assignment edit

As part of the class I am taking, I was assigned to edit this page. I have added a couple of changes below that I was thinking of making, please comment on accuracy and relevancy, thank you! Gkw11 (talk) 18:10, 26 November 2011 (UTC)Reply

How can we be sure that your teacher approves of you asking for help in this way? Nadiatalent (talk) 19:21, 26 November 2011 (UTC)Reply

It is part of the assignment to put the suggested changes in this discussion section. Here are his words: "VERY IMPORTANT #1: If you havent posted to wikipedia that you will be making changes, do so now. Remember that it is important to put suggested changes in the sandbox as well to get feedback - going in and making changes without doing so is considered poor form." Gkw11 (talk) 17:51, 27 November 2011 (UTC)Reply

Wikipedia:Sandbox is for trying out how your changes will look (formatting, etc.), so that when you put them on the Polylepis page they don't require so much work from other editors. Nadiatalent (talk) 00:56, 28 November 2011 (UTC)Reply
I would comment that this text requires cleaning up. For example, genus and species names are set in italic font (which is coded like this Polylepis), though family, subfamily and tribe are not italicized. It is not necessary to duplicate in text the information that already appears in the taxobox. You need to carefully read over what you have written and correct, for example "presence presence or absence". Links to appropriate wikipedia pages should be used, which are coded with double square brackets (e.g., trichomes). Some of what you have written is not easy to understand, for example I don't know what "spurs" are. "Spore Dispersal: The fruits of all species must be wind dispersed because members of the genus are trees and are thus too tall for animals (presumably mammals) to brush against." doesn't make much sense to me. We don't use the term "spore" for seeds in English. "Few trees" and "A few trees" means very different things in English. Nadiatalent (talk) 19:01, 29 November 2011 (UTC)Reply
Thank you very much for the feedback! I appreciate it very much and I will make the appropriate changes. The work is still being edited (that was only the first draft) so it will be much improved before the final copy. Thanks again, Gkw11 (talk) 18:38, 30 November 2011 (UTC)Reply

Taxonomy: The genus Polylepis most likely arose from hybridization between two Andean ancestors . Taxonomically, the genus Polylepis is placed within the family Rosaceae to the subfamily Rosoideae, and tribe Sanguisorbeae. There are several characteristics that are important taxonomically to distinguish between species of Polylepis, for example: 1) The amount of leaf congestion, 2) Presence presence or absence of spurs and their size and vestiture, 3) Presence presence or absence and type of trichomes, 4) Sizesize, shape, thickness and vestiture of leaflets. The most important taxonomic character, however, is the leaflets.

Habitat and Distribution: Species in the genus Polylepis are confined to the high tropical South American Andes Mountains, with the most abundant concentrations of Polylepis ranging from northern Venezuela to northern Chile and adjacent Argentina. One known group of extra-tropical population of Polylepis is distributed in the mountains of Northwestern Argentina. Most species of Polylepis grow best at high elevations, between 3500 to 5000 meters; although there are occurrences of species at low altitudes, as low as 1800 meters. These low altitude species are mixed with montane forest, indicating that components of the genus could have been present in western South America during the Miocene Period or even earlier. It is extremely rare for tree species to live at such altitudes, making Polylepis one of the highest natural occurring trees along with the conifers of the Himalayan Mountains. Polylepis rosaceous grows as shrubby trees on steep, rocky slopes above cloud forest. P. tomentella, reaches 4,800 m; the highest elevation of tree growth in the world.16 There is much debate on whether Polylepis was forced to occupy such extreme elevation habitats due to habitat destruction by human interference. Physiological tolerances for growth at these elevations are subject to considerable debate among scientists, but evidence indicates that even before severe decimation by man, high elevation trees were limited in their distribution by the presence of specialized microhabitats. The harsh environment in which many species of Polylepis grows contorts the growth of the tree’s stems and branches. This abnormal growth is often associated with windy, cold or arid habitats. The climate of the South American Andes changes drastically throughout the region creating lots of microhabitats. Overall, the climate consists of short southern summers when temperatures are warm and rainfall is high and long winters when temperatures are low and rainfall is limited. The temperature and amount of rainfall also depend on which side of the mountain (eastern or western side), elevation and latitude.

Spore Dispersal: The fruits of all species must be wind dispersed because members of the genus are trees and are thus too tall for animals (presumably mammals) to brush against. However, the elaboration of spines on the fruits of many taxa would argue for animal dispersal although wind dispersal undoubtedly predominates in P. australis. Numerous birds forage or live in Polylepis trees and it is possible that they disperse fruits caught in their feathers. There are no records of birds eating Polylepis fruits.

Reproduction: The pollen of Polylepis can be described in the following way: monads, isopolar, more or less spheroidal to slightly oblate in shape. The fruits of Polylepis are actually achenes composed of the floral cup fused to the ovary. Fruits of all species are indehiscent and one seeded. The surface of the fruit of different species has ridges, knobs, spines or wings. There are no definite sites for the placement of these different types of protuberances that appear irregularly over the surface. The type of protuberance, wings verses spines, or knobs versus wings, is useful for distinguishing between species.

Conservation:

In early 2005 the conservation project became a reality and would be carried out until 2008. It was promoted by the Department of Environment, the Mountain Institute - and had the management support - of the Ancash Association and International Conservation (IC). In respect to conservation of biodiversity as a component of sustainable development, this project represented a model of international environmental and social corporate responsibility for the mining sector in Peru and the world The project's direct environmental outcome was the restoration and conservation of the Polylepis forests, which contributed to the development of a forest corridor linking Conchucos Valley between the Huascaran National Park and the Huayhuash Reserve in the Ancash Department. They estimate that a total area of 200,000 hectares benefited from this project. Of these, 50,000 were directly acted upon. The long-term vision of the project was to generate sufficient ability among the participating communities to continue restoration activities and forest management, so that the corridor continue to grow and build connections while generating economic benefits for communities, including jobs, access to nurseries and firewood in secondary forests dedicated to sustainable management. The project’s primary component was sustainability through training and long-term commitment.

Human Use: Since Polylepis inhabits extremely high elevations, it has played an important role in the culture of various Andean Indian groups by providing building material and firewood. Also, the woodlands themselves constitute a distinctive habitat for other organisms allowing for the creation of endemic fauna in the future. The trees are also used as decoration; planted in front of buildings and houses. As a result of people expanding their reach, Polylepis have been subjected to harvest for firewood, the clearing of woodlands for pastureland and the destruction of seedlings by domesticated animals. Few trees have been found growing on level ground; in turn they are located on “inaccessible” slopes. Gkw11 (talk) 18:19, 26 November 2011 (UTC)Reply