Longleaf Pine
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Longleaf Pine Conservation status: Vulnerable | ||||||||||||||||
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Missing image Longleaf_8246.JPG Longleaf Pine Pinus palustris forest, near Georgetown, South Carolina | ||||||||||||||||
Scientific classification | ||||||||||||||||
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The Longleaf Pine (Pinus palustris) is a pine native to the southeast United States, found along the coastal plain from eastern Texas to southeast Virginia.
It reaches a height of 30-35 m (100-115 ft) and a diameter of 0.7 m (28"). In the past, they reportedly grew to 47 m (154 ft) with a diameter of 1.2 m (47").
The bark is thick, reddish-brown, and scaly. The dark green, needle-like leaves occur in bundles of three. They are often twisted and are remarkably long 20-45 cm (8-18") in length. It is one of the two southern pines with long needles, the other being Slash Pine.
The cones, both male (catkins) and female (cones), are initiated during the growing season before buds emerge. Male cones begin forming in their buds in July, while female conelets are formed during a relatively short period of time in August. Pollination occurs early the following spring, with the male cones 3-8 cm (1-3") long. The female (seed) cones mature in about 20 months from pollination; when mature they are yellow-brown in color, 15-25 cm long, 5-7 cm broad opening to 12 cm (6-10" long, 2-2½" broad opening to 5" broad), and have a small but sharp downward-pointing spine on the middle of each scale. The seeds are 7-9 mm long, with a 25-40 mm wing (1/3" long, with a 1 - 1¾" wing).
Longleaf Pine takes 100 to 150 years to become full size and can live to 300 years old. When young, they grow a long taproot, which is usually 2-3 m (6-10 ft) long; by maturity they have a wide spreading lateral root system with several deep 'sinker' roots. It grows on well-drained, usually sandy soil, often in pure stands. The scientific name meaning "of marshes" is a misunderstanding on the part of Philip Miller who described the species, from seeing Longleaf Pine forests with temporary winter flooding.
Longleaf Pine is also known as Southern Yellow Pine or Longleaf Yellow Pine, and in the past as Pitch Pine (dropped as it caused confusion with Pitch Pine, Pinus rigida).
Ecology
Longleaf Pine is highly resistant to fire. Periodic natural wildfire selects for this species by killing other trees, leading to open Longleaf Pine forests or savannas. New seedlings do not appear at all tree-like and resemble a green fountain of needles. This form is called the grass stage. During this stage, which lasts for 5-12 years, growth is very slow, and the tree may take a number of years simply to grow ankle-high. Then it makes a growth spurt, especially if the is no tree canopy above it. In the grass stage, it is very resistant to grass fires, which burn off the ends of the needles, but the fire cannot penetrate the tightly packed needle bases to reach the bud.
Longleaf Pine forests are rich in biodiversity. The Red-cockaded Woodpecker is dependent on Longleaf Pine forests, and is now endangered as a result of this decline. Longleaf Pines seeds are large and nutritious, forming a significant food source for birds (notably the Brown-headed Nuthatch) and other wildlife.
Uses
Vast forests of Longleaf Pine once were present along the southeastern Atlantic coast and Gulf Coast of North America. These forests were the source of naval stores - resin, turpentine, and timber - needed by merchants and the navy for their ships. They have been cutover since for timber and usually replaced with faster growing Loblolly Pine and Slash Pine, for agriculture, and for urban/suburban development. Due to this deforestation and over-harvesting, only about 3 per cent of the original Longleaf Pine forest remains, and little new is planted.
The yellow, resinous wood is used for lumber and pulp. Boards cut years ago from virgin timber were very wide, up to 1 m (3 ft), and a thriving salvage business obtains these boards from demolition projects to be reused as flooring in upscale homes.
The stumps and taproots of old trees become saturated with resin and will not rot. Farmers sometimes find old buried stumps in fields, even some that were cleared a century ago, and these are usually dug up and sold as "fat lighter" or "lighter wood" which is in demand as kindling for fireplaces, wood stoves, and barbecue pits. In old growth pine the heartwood of the bole is often saturated in the same way. When boards are cut from the fat lighter wood, they are very heavy and will not rot. But buildings constructed of them are quite flammable and make extremely hot fires.
The Longleaf Pine is the official state tree of North Carolina and Alabama.
External links
- Flora of North America Online: Pinus palustris (http://www.efloras.org/florataxon.aspx?flora_id=1&taxon_id=200005348)
- Gymnosperm Database: Pinus palustris (http://www.botanik.uni-bonn.de/conifers/pi/pin/palustris.htm)de:Sumpfkiefer