baumzaehlen - Primeval Forests & Their Trees

©2017copyright christoph hase

Yellowstone National Park, Wyoming, USA

 

Yellowstone National Park (8983 km2) is famous for its geothermic features and bison herds, but here we are interested in its large forested wildernesses.


Tree species diversity is low and identification easy. Excluding areas at high altitudes, Opens internal link in current windowPinus contorta var. latifolia (lodgepole pine) dominates everywhere. These forests have been formed after wildfires. P. contorta, with its thin bark, is not well-adapted to survive fire but the serotinous (opened by heat) cones effect rapid regeneration in burned areas, allowing it to maintain its dominance1. The theoretical climax species on most of the park would be Opens internal link in current windowAbies lasiocarpa (subalpine fir)2, but both this and Opens internal link in current windowPicea engelmannii (Engelmann spruce) seem to invade forests extremely slowly. In some very dry and infertile sites P. contorta is even the theoretical climax species3. Annual precipitation is 280-1800 mm 2 and elevation 1610-3462 m. Average annual temperature at 2000 m is approx. 2–3°C.

 

Off-trail hiking is generally easy. Camping is allowed only on designated sites.

 

References:

 

1       Agee, J. K. (1998): Fire and pine ecosystems. In Richardson, D. M. (ed.): Ecology and Biogeography of Pinus. Cambridge.

2       Despain, D. G. (1990): Yellowstone Vegetation. Roberts Rinehart.

3       Despain, D. G. (1983): Nonpyrogenous climax lodgepole pine communities in Yellowstone National Park. Ecology, 64, 231–4.

 

Official site:

 

http://www.nps.gov/yell/index.htm

 

Pinus contorta var. latifolia (lodgepole pine) forest, elev. 2375 m.
Yellowstone River. Pinus contorta var. latifolia (lodgepole pine) forest. A bison, right background.
Lower Falls. Pinus contorta var. latifolia (lodgepole pine) forest.
Grand Canyon of Yellowstone. On the slopes mainly Pinus contorta var. latifolia (lodgepole pine).
Pinus contorta var. latifolia (lodgepole pine), left; Abies lasiocarpa (subalpine fir), right.
Pinus contorta var. latifolia (lodgepole pine) in Bechler Meadows. In the background P. contorta dominated forest.
Bechler Meadows. Pinus contorta var. latifolia (lodgepole pine) forest. Also Abies lasiocarpa (subalpine fir), very narrow crowns on the right.
Pseudotsuga menziesii var. glauca (Rocky Mountain Douglas-fir) in Pinus contorta var. latifolia (lodgepole pine) forest.
Bechler Meadows. Pinus contorta var. latifolia (lodgepole pine) forest. Also Pseudotsuga menziesii var. glauca (Rocky Mountain Douglas-fir), the taller trees.
Picea engelmannii (Engelmann spruce) dominated forest at 2360 m. Also two dead Pinus contorta var. latifolia (lodgepole pine), foreground and next right.
Picea engelmannii (Engelmann spruce) - Pinus contorta var. latifolia (lodgepole pine) - Abies lasiocarpa (subalpine fir) forest on Yellowstone Lake. The tallest trees are P. engelmannii. Elev. 2360 m.
Pinus albicaulis (whitebark pine) in Pinus contorta var. latifolia (lodgepole pine) forest.
Populus tremuloides (quaking aspen).
Alnus incana subsp. tenuifolia (mountain alder).