Scientific name: Pinus taeda Linnaeus 1753

Synonyms: Pinus lutea Walter, Pinus mughoides E.H.L.Krause, Pinus taeda var. alopecuroidea Aiton, Pinus taeda var. mughoides E.H.L.Krause, Pinus taeda var. tenuifolia Aiton

Common names: Loblolly pine, Southern pine (English)

Description

Tree to 35(-45) m tall, with trunk to 1(-1.5) m in diameter. Bark dark brown, thick, scaly, breaking up into broad, interlacing ridges or irregular, small plates separated by narrow furrows. Crown dome-shaped, deep to shallow, generally dense, with numerous slender, upwardly angled branches densely clothed with foliage near the tips. Twigs yellowish brown to reddish brown, hairless, rough with the bases of scale leaves. Buds 10-15(-20) mm long, slightly resinous. Needles in bundles of (two or) three, each needle (8-)10-17(-23) cm long, thick but flexible, twisted, pointing a little forward, lasting (2-)3 years, dark yellowish green or sometimes grayish green. Individual needles with inconspicuous, evenly spaced lines of stomates on both the inner and outer faces, and two (to seven) resin canals at the corners and in between, mostly midway between the needle surface and the two-stranded midvein. Sheath 15-20(-25) mm long, weathering to 10-15 mm and persisting and falling with the bundle. Pollen cones (1.5-)2-4 cm long, yellowish brown, sometimes with a reddish blush. Seed cones (6-)7-10(-12) cm long, egg-shaped to cylindrical, with 120-160 seed scales, green before maturity, ripening dull yellowish brown, opening widely to release the seeds and then sometimes remaining for up to 3-4 years before falling with the extremely short stalk. Seed scales gently tapering, the exposed face horizontally diamond-shaped, from nearly flat on the upper scales to noticeably protruding at the base of the cone, crossed by a distinct ridge topped by an umbo bearing a strong, sharp, downwardly pointing spine. Seed body 5-7 mm, the firmly attached wing another 15-23 mm longer.

The scientific name of the very resinous loblolly pine was simply borrowed by Linnaeus from the ancient Roman name for torches and the pitchy pines they were made from.

Coastal Plain and Piedmont of the southeastern United States, from southwestern New Jersey to central Florida, west to eastern Texas and southeastern Arkansas, with a gap in the Mississippi River valley. Forming pure stands or mixed with other pines and hardwoods on a wide variety of sites from swamp margins to old fields; 0-700 m.

Conservation Status

Red List Category & Criteria: Least Concern

Pinus taeda is a widespread and abundant species that is currently increasing its area of occupancy. It is assessed as Least Concern. The population is vast and increasing, regaining ground formerly lost to clearing of forest for agriculture.

Pinus taeda is widely distributed on the Atlantic Coastal Plain and extends into the plateaus and foothills around the southern Appalachians to ca. 700 m a.s.l. but avoids the Mississippi floodplain. The climate is warm-temperate and moist, with mild winters and long, hot summers; annual precipitation is between 1,000 and 1,500 mm. This pine forms extensive stands on low, sandy knolls in the 'prairie swamps' along the Gulf of Mexico; in the inland parts of the coastal plain it occurs on river floodplains and old river terraces with deep, relatively dry sandy or loamy soils. This species can form pure stands resulting from pioneer invasions after forest disturbance or onto abandoned fields, or in mixed pine-dominated forests with several other species of Pinus. It is also a component of forest types dominated by broad-leaved trees, especially species of oak (Quercus spp.) as well as Acer rubrum, Liriodendron tulipifera, Fagus grandifolia, Fraxinus spp., and Diospyros virginiana in upland sites. In the coastal swamplands Magnolia grandiflora, Nyssa aquatica, Quercus michauxii, Carya aquatica, and Ulmus americana are common associates of Pinus taeda, together with other pines and an undergrowth of shrubs and palmettos (dwarf palms).

Loblolly pine is commercially the most important pine of the southern United States, where it makes up over half of the standing pine volume. It is much used in plantation forestry and is a fast grower. Its sawn wood properties are not of sufficient quality to be used in high grade construction and manufacture, and its fast growth and great volume is consequently put mainly to the wood pulp industry for paper and other long-fibre products. In urban settings the species finds a use as shelterbelt trees and for soil stabilization, again thanks to its rapid growth. This capacity for quick volume increase has also been reason to investigate its suitability as a biomass producer for the generation of energy. Plantations for this purpose are now being exploited and its use may well increase in future. Loblolly pine has also been introduced in many countries and is grown in forestry plantations on a large scale in South Africa, Brazil, China, Australia, and New Zealand. This species is little used in horticulture (except the use of leaf litter as a mulch); more northern provenances may well be hardy to light frosts. It has a preponderance to invasiveness.

No specific threats have been identified for this species. This species is known from numerous protected areas within its range.

References

Farjon, A. (2010). A Handbook of the World's Conifers. Koninklijke Brill, Leiden.
Eckenwalder, J.E. (2009) Conifers of the World: The Complete Reference. Timber Press, Portland.
IUCN Red List of Threatened Species, International Union for Conservation of Nature and Natural Resources. Cambridge, UK /Gland, Switzerland