Posts Tagged ‘table mountain pine’

The Chimney Top Fire

June 24, 2017

The Chimney Top is a series of dry rocky ridges located in the Great Smoky Mountains National Park where slate, schist, and phylite overlay erosion-resistant sandstone.  In some places precipitation has eroded away the top rocks, exposing the sandstone, and the formations resemble chimney tops, hence the name.  Last November, 2 unnamed juveniles set the surrounding forest on fire.  Drought conditions fed the fire, and it was fanned by 80 mph mountain wave winds.  Hot air from the fire rose up the mountain and when it met stable air, it ricocheted and accelerated downward in waves.  The fire burned over 15 square miles and spread into neighboring Gatlinburg, Tennessee, killing 16 people, 2 black bears, and uncounted small animals.  Yet, this forest will recover because many of the plant species growing on the ridge are well adapted to fire and in some cases even dependent upon it.

Pinus-pungens-04.JPG

Needles and cone of the table mountain pine.  This species depends on fire to open its cones.

Maitohorsma (Epilobium angustifolium).JPG

Fireweed also depends on fire.

Image may contain: cloud, sky, mountain, tree, outdoor and nature

The Chimney Tops.  Erosion resistant rock explains the chimney-like formations.

Photo of a burned ridge on Chimney Top.

The Chimney Top environment consists of rock chestnut oak (Quercus montana), table mountain pine (Pinus pungens), and heath balds.  Rock chestnut oak is fire resistant, and it thrives in the rocky shallow soils on the ridge.  Table mountain pine also grows well in the shallow soils, and it depends upon fire to open its seed cones.  Although long exposure to hot sun opens table mountain pine cones, the process is best facilitated by fire.  Park service employees noted a rain of pine seeds in the air a few days after the fire.  In 5 years the burned over ridges will be covered with pine saplings and fireweed.  Some heath balds completely burned to the ground–an unusual occurrence here because this region is the rainiest spot east of the Mississippi.  Heath balds are evergreen shrub communities consisting of mountain laurel (Kalmia latifolia), Catawba rhododendron (Rhododendron catawbiense), various species of blueberries (Vaccinium sp.) and huckleberries (Gayluccia sp.), and 1 deciduous tree–mountain ash (Sorbus aucuparia).  Heath balds are often adjacent to grassy balds and surrounded by forests of red spruce and hemlock.  Heath shrubs thrive on shallow acid soils located on mountain slopes.  Both heath and grassy balds are of ancient origin.  (See: https://markgelbart.wordpress.com/2016/05/16/the-extinct-helmeted-musk-ox-bootherium-bombifrons-and-appalachian-grassy-balds-during-the-pleistocene/ )  Scientists studied heath balds and discovered they grow on a layer of peat underlain by charcoal.  This suggests heath balds occasionally do burn completely, yet regrow in the same location.  This fire gives scientists the first chance to ever witness the rebirth of a heath bald.

Related image

Heath bald.

Forests are resilient.  The area in the photo below was clear cut during 1910.  The original forest consisted of chestnut, oak, and hemlock; many with trunks 5 feet in diameter.  The destruction of this locality spurred the creation of the Great Smoky Mountains National Park in 1926.  The 2nd growth forest that replaced the original tract is not as impressive but at least it is green.

Image may contain: mountain, sky, plant, cloud, grass, tree, outdoor and nature

This area was clear cut in 1910.  It has nicely recovered but is not as impressive as it was originally.

Advertisements