Pinaceae -- Pine family

    W. D. Boyer

    Longleaf pine (Pinus palustris), whose species name means "of  the marsh," has been locally referred to as longstraw, yellow,  southern yellow, swamp, hard or heart, pitch, and Georgia pine. In  presettlement times, this premier timber and naval stores tree grew in  extensive pure stands throughout the Atlantic and Gulf Coastal Plains. At  one time the longleaf pine forest may have occupied as much as 24 million  ha (60 million acres), although by 1985 less than 1.6 million ha (4  million acres) remained.

longstraw pine, southern yellow pine, Georgia pine

Pinus palustris P. Mill., longleaf pine, is found in the Atlantic and Gulf coastal plains from southeastern Virginia to central Florida and west to eastern Texas, and in the Piedmont region and Valley and Ridge province of Georgia and Alabama. Longleaf pine is a long-lived, native, evergreen conifer with scaly bark. Needles are in bundles of 3; they are shiny, dark green, and 8 to 15 inches long. Cones are 6 to 8 inches long. Mature trees attain a height of 100 to 120 feet and 2½ feet in diameter. Its seeds are the largest of all southern pines. It has extensive lateral roots and a taproot that grows 8 to 12 feet long.

(key to state/province abbreviations)
AL      FL      GA      HI      LA      MS      NC      SC      TX      VA

Longleaf pine occurs in the Atlantic and Gulf coastal plains from southeastern Virginia to central Florida and west to eastern Texas. It is found in the Piedmont Region and Valley-and-Ridge Province of Georgia and Alabama [7,31].

The natural range of longleaf pine includes most of the Atlantic and  Gulf Coastal Plains from southeastern Virginia to eastern Texas and south  through the northern two-thirds of peninsular Florida. The species also  grows in the Piedmont, Ridge and Valley, and Mountain Provinces of Alabama  and northwest Georgia.

     
- The native range of longleaf pine.

Pinus palustris Mill.:
United States (North America)
China (Asia)

Note: This information is based on publications available through Tropicos and may not represent the entire distribution. Tropicos does not categorize distributions as native or non-native.

A once-abundant tree which has reduced in area of occupancy from 24 million ha to 1.6 million ha in 1985. Subpopulations continue to become increasingly scattered and restricted to parks and reserves.

United States

Origin: Native

Regularity: Regularly occurring

Currently: Present

Confidence: Confident

Type of Residency: Year-round

Longleaf pine grows best in a warm, wet, temperate climate with an annual precipitation range of 43 to 69 inches. Although the species occurs in a wide variety of upland and flatwood sites, it is common on sandy, infertile, well-drained soils, mostly below 660 feet elevation.

Longleaf pine is distributed throughout the Southeast. For a current distribution map, please consult the Plant Profile page for this species on the PLANTS Website.

Trees to 47m; trunk to 1.2m diam., straight; crown rounded. Bark orange-brown, with coarse, rectangular, scaly plates. Branches spreading-descending, upcurved at tips; twigs stout (to 2cm thick), orange-brown, aging darker brown, rough. Buds ovoid, silvery white, 3--4cm; scales narrow, margins fringed. Leaves (2)--3 per fascicle, spreading-recurved, persisting 2 years, 20--45cm ´ ca. 1.5mm, slightly twisted, lustrous yellow-green, all surfaces with fine stomatal lines, margins finely serrulate, apex abruptly acute to acuminate; sheath 2--2.5(--3)cm, base persistent. Pollen cones cylindric, 30--80mm, purplish. Seed cones maturing in 2 years, quickly shedding seeds and falling, solitary or paired toward branchlet tips, symmetric, lanceoloid before opening, ovoid-cylindric when open, 15--25cm, dull brown, sessile (rarely short-stalked); apophyses dull, slightly thickened, slightly raised, nearly rhombic, strongly cross-keeled; umbo central, broadly triangular, with short, stiff, reflexed prickle. Seeds truncate-obovoid; body ca. 10mm, pale brown, mottled darker; wing 30--40mm. 2 n =24.

Longleaf pine is a long-lived, native, evergreen conifer with scaly bark. Needles are 8 to 18 inches (20-46 cm) long; cones are 6 to 8 inches (15-20 cm) long. Mature trees attain a height of 100 to 120 feet (30.5-36.6 m) and have the potential of living 4 to 5 centuries. The longleaf pine seed is the largest of all southern pines. On good sites, longleaf pine grows an 8- to 12-foot-long (2.4-3.7 m) taproot and extensive lateral roots [7,38,54].

Tree, Evergreen, Monoecious, Habit erect, Trees without or rarely having knees, Tree with bark rough or scaly, Young shoots 3-dimensional, Buds not resinous, Leaves needle-like, Leaves alternate, Needle-like leaf margins finely serrulate (use magnification or slide your finger along the leaf), Leaf apex acute, Leaves > 5 cm long, Leaves > 10 cm long, Leaves yellow-green above, Leaves yellow-green below, Leaves not blue-green, Leaves white-striped, Needle-like leaves triangular, Needle-like leaves twisted, Needle-like leaf habit drooping, Needle-like leaves per fascicle mostly 3, Needle-like leaf sheath persistent, Twigs glabrous, Twigs viscid, Twigs not viscid, Twigs without peg-like projections or large fascicles after needles fall, Berry-like cones orange, Woody seed cones > 5 cm long, Seed cones bearing a scarlike umbo, Umbo with obvious prickle, Bracts of seed cone included, Seeds brown, Seeds winged, Seeds unequally winged, Seed wings prominent, Seed wings equal to or broader than body.

Trees to 45 m tall; trunk to 1.2 m d.b.h. in native range; bark orange-brown, with coarse, oblong, scaly plates; crown rounded; branches spreading-descending, upcurved at tips; branchlets orange-brown, aging darker brown, stout, rough; winter buds silvery white, ovoid, 3-4 cm, scales fringed at margin. Needles spreading-recurved, (2 or)3 per bundle, yellow-green, slightly twisted, 20-45 cm × ca. 1.5 mm, stomatal lines present on all surfaces, base with persistent sheath 2-2.5(-3) cm, margin finely serrulate. Seed cones solitary or paired toward branchlets tips, sessile or rarely shortly pedunculate, dark brown, ovoid-cylindric when open, 15-25 cm, maturing in 2 years, then quickly shedding seeds and falling. Apophyses dull, nearly rhombic, slightly thickened and raised, strongly cross keeled; umbo broadly triangular, with a short, stiff, reflexed prickle. Seeds pale brown, mottled darker, truncate-obovoid, ca. 1 cm; wing 3-4 cm.

Pinus australis F. Michaux; P. longifolia Salisbury.

Pinus australis F. Michaux

More info for the terms: mesic, shrubs, swamp, xeric

Associated hardwoods on mesic coastal plain sites include southern red
oak (Quercus falcata), blackjack oak (Q. marilandica), water oak (Q.
nigra), flowering dogwood (Cornus florida), blackgum (Nyssa sylvatica),
sweetgum (Liquidambar styraciflua), persimmon (Diospyros virginiana) and
sassafras (Sassafras albidum). Associated hardwoods on xeric sandhill
sites include turkey oak (Q. laevis), bluejack oak (Q. incana), sand
post oak (Q. stellata var. margaretta), and live oak (Q. virginiana) [7].

Associated shrubs include gallberry (Ilex glabra), yaupon (I.
vomitoria), large gallberry (I. coriacea), wax-myrtle (Myrica
cerifera), shining sumac (Rhus copallina), blueberry (Vaccinium spp.),
huckleberry (Gaylussacia spp.), blackberry (Rubus spp.), saw palmetto
(Serena repens), sweetbay (Magnolia virginiana), swamp cyrilla (Cyrilla
racemiflora), and buckwheat-tree (Cliftonia monophylla) [7].
In longleaf pine's western range, groundcover includes bluestem
(Andropogon spp.) and panicum (Panicum spp.). In its eastern range,
pineland threeawn or wiregrass (Aristida stricta) is the primary
groundcover [7].

The published classifications listing longleaf pine as a dominant or
codominant species in community types (cts) are presented below:
Area                         Classification                 Authority

e TX, LA, MS          general veg. cts              Bridges & Orzell 1989

AL                            forest cts                       Golden 1979

SC                            veg. cts                         Nelson 1986

se US; Gulf Coast      general forest cts           Pessin 1933

se US                        general forest cts           Waggoner 1975

NC                            veg. cts                         Wells 1928

More info on this topic.

This species is known to occur in association with the following Rangeland Cover Types (as classified by the Society for Range Management, SRM):

More info for the terms: cover, hardwood

SRM (RANGELAND) COVER TYPES [55]:

808 Sand pine scrub

809 Mixed hardwood and pine

810 Longleaf pine-turkey oak hills

811 South Florida flatwoods

812 North Florida flatwoods

813 Cutthroat seeps

820 Everglades flatwoods

More info on this topic.

This species is known to occur in association with the following cover types (as classified by the Society of American Foresters):

More info for the term: cover

SAF COVER TYPES [19]:

69 Sand pine

70 Longleaf pine

71 Longleaf pine-scrub oak

75 Shortleaf pine

81 Loblolly pine

82 Loblolly pine-hardwood

83 Longleaf pine-slash pine

84 Slash pine

111 South Florida slash pine

More info on this topic.

This species is known to occur in association with the following plant community types (as classified by Küchler 1964):

KUCHLER [27] PLANT ASSOCIATIONS:

K111 Oak-hickory-pine

K112 Southern mixed forest

K115 Sand pine scrub

K116 Subtropical pine forest

More info on this topic.

This species is known to occur in the following ecosystem types (as named by the U.S. Forest Service in their Forest and Range Ecosystem [FRES] Type classification):

ECOSYSTEMS [21]:

FRES12 Longleaf-slash pine

FRES13 Loblolly-shortleaf pine

FRES14 Oak-pine

Longleaf pine grows in a warm, wet, temperate climate with an annual precipitation of 43 to 69 inches (109-175 cm). The species occupies a wide variety of upland and flatwood sites, but is most common on sandy, infertile, well-drained soils. Soil types include Ultisols, Entisols, and Spodosols. Elevations range from near sea level to 1,970 feet (600 m), although most longleaf pine grows below 660 feet (200 m) [7].

Longleaf pine is native to a wide variety of sites ranging from wet,  poorly drained flatwoods to dry, rocky mountain ridges. Elevations range  from barely above sea level near the beaches on the lower Coastal Plain up  to about 600 m (1,970 ft) in the mountains of Alabama. Most of the  longleaf pine forests are found on the Atlantic and Gulf Coastal plains at  elevations below 200 m (660 ft). Here the soils are largely derived from  marine sediments and range from deep, coarse, excessively drained sands to  poorly drained clays. For the most part, surface soils are sandy, acid,  low in organic matter, and relatively infertile. In the Mountain Province,  soils are derived largely from granite, quartzite, schist, phyllite, and  slate, while in the Ridge and Valley Province, soils are derived mostly  from sandstone, shale, limestone, and dolomite (21).

    Within the natural range of longleaf pine, three soil orders are of  major importance. Ultisols are the dominant order and cover most of the  southeastern United States outside of peninsular Florida. Ultisols most  commonly associated with longleaf pine are the Typic Paleudults and  Plinthic Paleudults. The other two soil orders are Entisols and Spodosols.  Deep, sandy Entisols, primarily Quartzipsamments, range from about 3 m (10  ft) above sea level in Florida up to about 185 m (600 ft) in Georgia and  the Carolinas. Entisols have not developed diagnostic horizons. They make  up the Sandhills of the Carolinas, Georgia, and northwest Florida and the  sand ridges in the central Highlands of peninsular Florida. Spodosols,  particularly Aquods, are typical of the flatwoods of the lower Coastal  Plain in Florida. They are wet, sandy soils with a fluctuating water table  that is at or near the surface during rainy seasons (8).

Longleaf pine grows in warm, wet temperate climates characterized by hot  summers and mild winters. Annual mean temperatures range from 16° to  23° C (60° to 74° F) and annual precipitation from 1090 to  1750 mm (43 to 69 in), the least being 1090 to 1270 mm (43 to 50 in) in  the Carolinas and Texas and the greatest along the Gulf Coast of Alabama,  Mississippi, and extreme west Florida. A distinct summer rainfall peak  occurs along the Atlantic Coast, being most pronounced in Florida. A  secondary rainfall peak in March becomes pronounced along the Gulf Coast.  Fall is the driest season of the year, although droughts during the  growing season are not unusual.

Dry sandy uplands, sandhills, and flatwoods; 0--700m; Ala., Fla., Ga., La., Miss., N.C., S.C., Tex., Va.

Systems

• Terrestrial

Cultivated. Fujian, Jiangsu, Jiangxi (Lu Shan), Shandong (Qingdao Shi), Zhejiang [native to SE United States]

Longleaf pine stands are successfully established by either seeding or vegetative reproduction. Seeds (including dormant seeds if prechilled) can be sown in the fall or spring, pressed into the soil at densities from 15 to 75 seedlings per square foot. Seeds germinate 1 to 2 weeks following seedfall. Germination requires mineral soil. The seed’s large size and persistent wing prevent it from penetrating through the litter. Seedlings are stemless after one growing season and this lasts from 2 to many years. During this grass-stage, the seedling develops an extensive root system, and the root collar increases in diameter. When the root collar diameter approaches 1 inch in diameter, height growth begins. A field-grown seedling grows 10 feet in 3 years once height growth is initiated. Branch production is delayed until the seedling reaches 10 to 16 feet in height.

Vegetative propagation is usually done by grafting. If grass-stage seedlings are top-killed, they can sprout from the root collar. Once height growth begins, sprouting ability decreases rapidly.

Heavy grazing can reduce tree density, significantly reducing establishment and causing crop failure.

The principal longleaf cover types are Longleaf Pine (Society of  American Foresters Type 70), Longleaf Pine-Scrub Oak (Type 71), and  Longleaf Pine-Slash Pine (Type 83) (12). Longleaf pine is also a minor  component of other forest types within its range: Sand Pine (Type 69),  Shortleaf Pine (Type 75), Loblolly Pine (Type 81), Loblolly Pine-Hardwoods  (Type 82), Slash Pine (Type 84), and South Florida Slash Pine (Type 111).

    Longleaf pine develops in close association with periodic surface fires.  The vegetation associated with longleaf pine reflects the frequency and  severity of burning. In the past, frequent fires resulted in open,  parklike stands of longleaf with few other woody plants and a ground cover  dominated by grasses. Ground cover in longleaf pine in the Coastal Plains  can be separated into two general regions, with the division in the  central part of south Alabama and northwest Florida. To the west, bluestem  (Andropogon spp.) and panicum (Panicum spp.)  grasses predominate; to the east, wiregrass (pineland threeawn, Aristida  stricta) is most common.

    With a reduction in fire occurrence, hardwoods and other pines encroach  on the longleaf forest. Within the range of slash pine (Pinus  elliottii), this species becomes increasingly important, leading to  the cover type Longleaf Pine-Slash Pine. Elsewhere loblolly and shortleaf  pines (P. taeda and P. echinata) as well as hardwoods  gradually replace the longleaf, eventually resulting in Loblolly  Pine-Hardwood (Type 82) or occasionally Loblolly Pine-Shortleaf Pine (Type  80). On poor, dry sandhills and mountain ridges, scrub hardwoods invade  the understory creating forest cover type Longleaf Pine-Scrub Oak and  finally Southern Scrub Oak (Type 72) as the pine disappears (12).

    Hardwoods most closely associated with longleaf pine on mesic Coastal  Plain sites include southern red, blackjack, and water oaks (Quercus  falcata, Q. marilandica, and Q. nigra); flowering dogwood (Cornus  florida); blackgum (Nyssa sylvatica); sweetgum (Liquidambar  styraciflua); persimmon (Diospyros virginiana); and sassafras  (Sassafras albidum). The more common shrubs include gallberry (Ilex  glabra), yaupon (I. vomitoria), southern bayberry (Myrica  cerifera), shining sumac (Rhus copallina), blueberry (Vaccinium  spp.), huckleberry (Gaylussacia spp.), and  blackberry (Rubus spp.). On xeric sandhill sites, the most  common associates are turkey, bluejack, blackjack, sand post, and dwarf  live oaks Quercus laevis, Q. incana, Q. marilandica, Q. stellata var.  margaretta, and Q. minima). On the dry clay hills and  mountains of Alabama, blackjack, post (Q. stellata) and southern  red oaks, and mockernut hickory (Carya tomentosa) are found with  longleaf pine. On low, wet flatwood sites near the coast, the most  conspicuous understory plants are gallberry and saw-palmetto (Serenoa  repens). Other common understory plants in low, wet Longleaf Pine or  Longleaf Pine-Slash Pine types are sweetbay (Magnolia virginiana),  swamp cyrilla (Cyrilla racemiflora), large gallberry (Ilex  coriacea), buckwheat-tree (Cliftonia monophylla), blueberries,  and blackberries.

Longleaf pine is less susceptible to most  damaging agents than the other southern pines and is a relatively low risk  species to manage. It is strongly resistant to fire, except as a small  seedling of less than 0.8 cm (0.3 in) root collar diameter and in early  height growth. It is also resistant to most pathogenic agents. The major  disease is the brown-spot needle blight. This disease causes serious  damage only to grass-stage seedlings. Continued severe defoliation by   brown-spot suppresses and eventually destroys seedlings. Once rapid height  growth begins, seedlings are no longer seriously afflicted. Seedlings  growing in the open are most vulnerable, particularly if the groundcover  is sparse; the disease usually does not seriously affect seedlings growing  under a pine overstory. Other diseases occasionally of economic importance  in local areas are pitch canker (Fusarium moniliforme var. subglutinans),  annosus root rot (Heterobasidion annosum) in thinned  plantations, cone rust (Cronartium strobilinum) near the coast,  and also the condition known as dry face of turpentined trees. Fusiform  rust (Cronartium quercuum f. sp. fusiforme) is rarely a  problem for longleaf pine (20).

    Many species of birds, mice, and squirrels feed on longleaf pine seeds,  the latter often taking them from unripe cones. Several species of ants  feed on germinating seeds and cotyledon seedlings. Cottontails as well as  other predators can destroy newly established seedlings. Grass-stage  seedlings are vulnerable to destruction by hogs, pales weevil (Hylobius  pales), and heavy livestock grazing. Pocket gophers cut seedlings off  just below the ground surface.

    Most seedling losses occur during the first year after establishment,  untimely drought being the greatest single hazard. Logging of the  overstory can destroy close to 50 percent of a seedling stand,  although actual damage depends on type and season of logging, volume  removed, and seedling size. Fire takes its toll of small, weak, or  diseased seedlings.

    Longleaf pine can be damaged by ice storms but is less susceptible to  ice damage than slash pine (19).

    The southern pine beetle (Dendroctonus frontalis) does not seem  to afflict the species severely. The black turpentine beetle (Dendroctonus  terebrans) can be a problem, especially on trees injured by  turpentining, logging, or fire. Perhaps the greatest single cause of  mortality in longleaf stands of pole and sawlog size is lightning, which  is often followed by infestation by bark beetles (Ips spp.).  Windthrow from hurricanes or tornados can cause heavy losses locally. Long  term observations throughout the longleaf region have shown an average  annual mortality of 1 tree per hectare (0.4/acre) in mature longleaf pine  stands (4).

More info for the terms: fuel, hardwood

Prescribed burning in longleaf pine stands is used to control brown-spot needle blight, stimulate height growth, reduce excess fuel, control understory hardwoods, improve wildlife habitat, thin stands, and prepare a mineral seedbed [18,54].

Fire consumes foliage infected by brown-spot needle blight as well as inoculum in fallen leaves [29,54]. Burning is recommended when infection levels are greater than 20 percent and grass-stage root collars are larger than 0.3 inches (0.8 cm) in diameter or height-growth stage seedlings root collars are greater than 1.5 inches (3.8 cm). If the infection rate is higher than 20 percent, a high percentage of affected seedlings will die from the fire [18,35,45].

Annual spring fires are recommended to initiate height growth once grass-stage seedlings are large enough to withstand fire. In the spring, the green grass keeps the fire cool, and buds are protected by long sheaths of needles. However, grass-stage seedlings grown on poor sites may not tolerate light fire [12]. Once height growth begins, the stand should not be burned for several years and then burned less frequently [23].

Late annual spring fires are recommended to gain control of hardwoods. Summer fires are also effective, but the risk of pine mortality is increased [8]. Hardwoods are susceptible to fire in the late spring and summer because root reserves are low. Once hardwood populations are reduced, winter fire at 5-year intervals maintains longleaf pine stands, and enables a single fire in the spring or summer before seedfall to expose the necessary mineral soil seedbed [18,53].

Although longleaf pine regeneration is rarely excessive [2], a stand can be thinned by fire. In Alabama, a prescribed winter fire thinned a 1-year-old stand from 177,000 seedlings per acre (437,000/ha) to 6,300 per acre (15,600/ha) [33].

Frequent late spring or early summer fires are necessary to recreate the longleaf pine-grassland savannahs that were common in presettlement times [44].

More info for the terms: fire use, fuel, prescribed fire

The Fire Case Study Imperata cylindrica in a Florida sandhill
longleaf pine community provides information on fuel loads, prescribed
fire use, and postfire response of juvenile longleaf pines on cogon
grass (Imperata cylindrica)-infested sites and uninfested sites.

More info for the terms: basal area, competition

Fire can stimulate height-growth initiation of grass-stage seedlings. After three annual spring fires in Louisiana, most grass-stage seedlings had initiated height growth. It is thought that height growth is initiated because fire reduces competition and brown-spot needle blight infection. Late spring or summer fires are more effective at promoting height growth than winter fires [12,13,23]. However, annual fires begun only 1 year after germination stunt height growth [20].

Once a seedling has entered the height-growth stage, fire damage can decrease growth. Annual fires have reduced basal area growth of young longleaf pine by 22 to 44 percent [54]. In Alabama, prescribed biennial fires begun in 14-year-old stands averaging 22 feet (6.7 m) in height and 3.2 inches (8.1 cm) in diameter reduced growth, even though no crown scorch was observed. The impact on growth of biennial fires worsened with time. The season of fire had no effect [6].

Older longleaf pine shows no growth loss if there is little or no needle scorch [29]. Seed production of mature trees is not affected by frequent fire.

Seed will germinate on mineral soil exposed by fire [7].

Trees in regularly burned stands develop a buttressed trunk which results in stump taper [1].

More info for the terms: crown fire, fire tolerant, litter, root collar

Open-grown grass-stage seedlings with root collar diameters smaller than 0.3 inch (0.8 cm) can be killed by light fire [7,29]. Under a pine overstory, light fire can kill seedlings smaller than 0.5 inch (1.3 cm) in diameter, because excess pine litter under the canopy makes the fire hotter [3,18,44]. In a prescribed winter fire in Alabama, 1-year-old seedlings with exposed root collars were more susceptible to fire than seedlings with root collars at or near the soil surface [33]. Larger grass-stage seedlings are highly resistant to fire.

In the height-growth stage, seedlings 1 to 3 feet (0.3-0.9 m) tall are extremely vulnerable to fire [20,29]. If the terminal bud is destroyed, the seedling will die [37]. Once a seedling is about 3.3 feet (1 m) tall, it is likely to survive low-severity ground fires [38]. After the sapling is 10 feet (3 m) tall, it is very fire tolerant [54]. Trees 10 inches (25 cm) in diameter and larger survive all but the most severe fires [10]. A high-severity crown fire kills some mature trees and nearly all trees smaller than 10 inches (25 cm) in diameter [20].

Longleaf pine needles were killed instantly when immersed in water at 147 degrees Fahrenheit (64 deg C) but survived 11 minutes at 126 degrees Fahrenheit (52 deg C) [14].

More info for the terms: competition, fire interval, fire regime, litter, natural, root collar, surface fire, tree

Longleaf pine is classified as fire-resistant [10,36]. It is ideally suited to a high-frequency, low-severity surface fire regime. The natural fire interval is every year to every 5 to 10 years [44]. Most natural fires are caused by lightning and occur in late spring and summer [37,44].

Longleaf pine has many adaptations to fire. The grass-stage seedling is resistant to fire. If top-killed, it sprouts from the root collar. Once the terminal bud develops, it is protected by a moist, dense tuft of needles. As the tuft burns towards the bud from the needle tips, water is vaporized. The steam reflects heat away from the bud and extinguishes the fire [37,38]. The bud also has scales for protection and a silvery pubescence that probably reflects heat [29,37].

During the grass-stage, the seedling invests heavily in a taproot and in root collar size. When height growth is initiated, often the year after a fire, the seedling uses its stored reserves to quickly grow a straight stem with no branches. After one growing season, the terminal bud is usually above the level of the next surface fire [37,38].

The bark becomes thick with age and insulates the cambium from heat. The scaly bark dissipates heat by flaking off as it burns [37,38].

In addition to fire resistant adaptations, longleaf pine has a pyrogenic strategy. Spring and summer fires are beneficial because they reduce competition and expose the mineral soil necessary for seed germination in the fall. Long, resin-filled needles have short persistence and form a highly flammable, well-aerated litter. Resin is also concentrated in the bole and roots of older trees and snags. These trees act as lightning receptors. A smoldering tree can ignite the ground several days or weeks later when the ground litter has dried out. Longleaf pine communities often have a grass understory that readily ignites. [28,37,43]. Because of open stands and high and open crowns, crown fires are rare [43].

More info on this topic.

More info for the term: competition

Longleaf pine is intolerant of shade and competition. With frequent fire, uneven-aged pure stands of longleaf pine form parklike savannahs [7,20,37]. Because longleaf pine regenerates in openings created by the death of mature trees, small clusters of trees of the same age are dispersed throughout the stand [43]. In the absence of frequent fire, longleaf pine is replaced by hardwoods and other southern pines [7,54]. Loblolly pine and shortleaf pine will invade and soon dominate a site of grass-stage longleaf pine [11]. Recruitment of longleaf pine ceases 15 years after fire. Invasion by hardwoods accelerates the decline of mature longleaf pine [24].

Longleaf pine is classified as a fire subclimax [18,19,20,45]. Lightning, which historically ignited the frequent fires, is a component of a long-term climatic pattern. As long as there is lightning, longleaf pine can perpetuate itself indefinitely on a site.

More info for the terms: competition, epigeal, litter, monoecious, root collar, tree

Seed production and dissemination: Longleaf pine is monoecious. It begins producing cones when it reaches about 30 years of age or 10 inches (25 cm) in diameter [18,38]. The best cone producers are 15-inch-diameter (38 cm) open-grown trees. Cones contain, on average, 35 seeds [7]. Longleaf pine masts every 7 to 10 years, but healthy trees will produce a fair to good seed crop every 3 to 4 years [2,37,38]. The winged seeds are dispersed a short distance by wind with 71 percent of the seeds falling within 66 feet (20 m) of the base of the parent tree [7].

Germination and seedling development: Seeds germinate 1 to 2 weeks after seedfall. Germination is epigeal and requires mineral soil. The seed's large size and persistent wing prevent it from penetrating through the litter. Seedlings are stemless after one growing season and this "grass-stage" lasts from 2 to many years [7,18,38]. It may last as long as 20 years if brown-spot needle blight or competition is severe [18,45]. During the grass-stage, the seedling develops an extensive root system, and the root collar increases in diameter. When the root collar diameter approaches 1 inch (2.5 cm) in diameter, height growth begins. An open-grown seedling grows 10 feet (3 m) in 3 years once height growth is initiated [7,37,54]. Branch production is delayed until the seedling reaches 10 to 16 feet (3-5 m) in height [43].

Vegetative reproduction: If grass-stage seedlings are top-killed, they can sprout from the root collar. Once height growth begins, sprouting ability decreases rapidly [7].

More info on this topic.

More info for the term: phanerophyte

RAUNKIAER [46] LIFE FORM:
Phanerophyte

More info for the term: tree

Tree

POSTFIRE REGENERATION STRATEGY [56]:
Crown-stored residual colonizer; short-viability seed in on-site cones
Off-site colonizer; seed carried by wind; postfire years one and two

Longleaf pine is intolerant of  competition, whether for light or for moisture and nutrients. The species  will grow best in the complete absence of all competition, including that  from other members of the species. Fortunately, as noted earlier, young  even-age longleaf pine stands break up rapidly into a broad range of size  classes, due to variability in duration of the grass stage. Stagnation is  almost never a problem. However, even suppressed trees in a stand will   slow the growth of dominant neighbors. Optimum stand density for  development of crop trees needs to be maintained by periodic thinning.  Given release from neighboring trees, dominant and codominant trees in an  over-dense stand will respond promptly with increased diameter growth, as  will some intermediate trees that retain crown ratios of 30 percent or  more. Suppressed trees, while they may continue to live, rarely respond to  release with improved growth.

Longleaf pine develop massive taproots that, in  mature trees, may extend to a depth of 2.4 to 3.7 m (8 to 12 ft) or more.  A hardpan can arrest downward growth of the taproot. If the hardpan is  close to the surface, windfirmness of the tree is reduced. Longleaf pines  develop extensive lateral root systems. Most lateral roots are within 0.3  m (1 ft), and nearly all within 0.6 m (2 ft), of the surface (29).

More info on this topic.

Longleaf pine seed develops in a 3-year process. Strobili are initiated during midsummer. Conelets emerge in late winter. Catkins emerge in November, then remain dormant until late winter. Pollination occurs from late February in the South to early April in the North. Fertilization does not occur until the following spring. Cones reach maturity in mid-September to mid-October after their second season of growth. Seed is dispersed from late October to November and the majority of seed falls in 2 to 3 weeks. Seed germinates 1 to 2 weeks later. Primary needles appear soon after germination and secondary needles about 2 months later [7,18].

Longleaf pine seedlings, if top killed,  can sprout from the root collar. Sprouting ability decreases sharply when  seedlings begin height growth. In one study, almost 40 percent of  seedlings cut off at the ground line during grass stage had living sprouts  a year later. Only 14 percent of seedlings up to 1.37 m (4.5 ft) in height  so treated developed sprouts, however, and those larger than this did not  sprout at all (14). Longleaf is not as easy to reproduce asexually as some  of the other southern pines. Cuttings can be rooted but the process is  difficult. Air-layering has met with limited success. Grafting has proven  to be a reliable technique, and this is now the most common method of  establishing seed orchards (28).

Longleaf pine differs from other southern  pines in that seeds germinate soon after they are dispersed. Given optimum  conditions, seeds germinate in less than a week after they reach the  ground. Prompt germination reduces the period of exposure to seed  predators, but newly germinated seedlings are susceptible to damage or  loss from animals, diseases, and weather uncertainties, which may include  high fall temperatures, drought, or extreme cold with a risk of frost  heaving in heavy soils (11).

    Seeds require contact with mineral soil for satisfactory germination and  establishment. Longleaf seeds, with their large wings, cannot easily reach  mineral soil through a heavy cover of grass and litter. The accumulated  material must be removed before seedfall, either mechanically or by  burning. Burning within a year of seedfall normally provides an adequate  seedbed. Lack of seedbed preparation can result in a regeneration failure.

    Germination of longleaf pine seed is epigeal (26). Newly germinated  seedlings have virtually no above-ground hypocotyl, and the cotyledons are  close to the ground line. The primary needles appear after germination and  the secondary needles about 2 months later. The epicotyl, or stem above  the cotyledons, does not elongate rapidly as in most other pines. Even in  the nursery, seedlings are virtually stemless after one growing season  (16). This stemless condition is one of the unique characteristics of  longleaf pine. It is referred to as a grass stage and may last 2 to many  years, depending on growth conditions. During this time, longleaf is most  susceptible to its major disease, the brown-spot needle blight, Scirrhia  acicola (11).

    While in the grass stage, seedlings develop extensive root systems.  Growth can be followed by observing the increase in root-collar diameter.  When it approaches 2.5 cm (1 in), active height growth is imminent.  Grass-stage seedlings, once they reach 0.8 cm (0.3 in) in root-collar  diameter, are highly resistant to fire, even during the growing season.  Seedlings in early height growth, up to a height of about 0.6 to 0.9 m (2  to 3 ft), become susceptible to damage by fire. Once beyond this stage,  longleaf pines are again fire resistant.

    Competition and brown-spot needle blight have great impact on the rate  of seedling development and together largely determine the duration of the  grass stage. Longleaf seedlings can be easily established and usually  survive for years under an overstory of parent pines. Growth, however, is  very slow. Seedlings respond promptly with an increased rate of growth  when released from overstory competition.

    Growth rate varies widely among individuals in a natural seedling stand,  and vigorous fast-growing seedlings express dominance early. The rapid  breakup of a seedling stand into a wide range of size classes reduces the  risk of stand stagnation. About 10 percent of a natural seedling stand  shows resistance to the brown-spot disease, and this gives them a growth  advantage that persists for many years. At age 24, trees that had little  or no brown-spot infection averaged 2.4 in (8 ft) taller than trees that  had 30 percent or more of their foliage destroyed by the disease as  seedlings (1).

    A low level of competition permits early initiation of height growth.  One longleaf pine plantation on a prepared site had nearly 60 percent of  the trees in active height growth by the end of the second growing season,  and over 90 percent by the end of the third. Early initiation of height  growth circumvented a brown-spot problem as the disease did not have time  to build up to serious proportions.

Tree size, crown class, stand  density, site quality, and, most important, genetic predisposition, all  affect cone production by an individual tree. The best cone producers are  dominant, open grown trees with large crowns, 38 cm. (15 in) or more in  d.b.h., with a past record of good cone production (11). Trees 38 to 48 cm  (15 to 19 in) in d.b.h. have produced an average of 65 cones annually  compared to 15 cones by trees from 25 to 33 cm (10 to 13 in) in d.b.h. The  number of sound seeds per cone varies widely and is related to size of  seed crop in a particular year. In good seed years there may be about 50  seeds per cone, in average years 35, and in poor years 15 (10).

    Seed production per hectare reaches a peak at stand densities between  6.9 and 9.2 m²/ha (30 to 40 ft²/acre) of basal area, assuming  that the stand is comprised of dominant-codominant trees of cone bearing  size (3). A shelterwood stand with a basal area of 6.9 m²/ha (30 ft²/acre)  produces three times as many cones per unit area as a stand of scattered  seed trees averaging 2.3 m²/ha (10 ft²/acre) in good seed years  (11).

    Throughout its range, longleaf pine in shelterwood stands produces seed  crops adequate for natural regeneration, about 2,500 cones per hectare  (1,000/acre), on the average of once every 4 to 5 years (11). However,  everything else being equal, good cone crops are more frequent in some  parts of the longleaf pine range than in others, so the general average  may be meaningless at a given location. The production of female strobili  is much less variable from place-to-place than is the production of mature  cones, indicating that geographic differences in cone production are due  more to conelet and cone losses than failure to produce conelets in the  first place (7).

    When a shelterwood stand is created by cutting back a stand of  substantially higher density, increased cone production resulting from  release does not occur until the end of the third growing season after  cutting (9). Release that occurs after conelet initiation has no effect on  that crop, other than promoting better conelet survival through reduced  stress in dry periods.

    Seeds are dispersed by the wind. Seed dispersal begins in late October  and continues through November, with the majority falling within a period  of 2 to 3 weeks. The time and duration of seed dispersal vary depending on  weather conditions. Dispersal range is limited, with 71 percent of sound  seeds falling within a distance of 20 m (66 ft) of the base of parent  trees (11).

    Longleaf seeds are the largest of the southern pines. The number of  cleaned seeds ranges from 6,600 to 15,400/kg (3,000 to 7,000/lb),  averaging 10,800/kg (4,900/lb) (26).

Like all species in the pine family,  longleaf pine is monoecious. The strobili of longleaf pine, both male  (catkins) and female (conelets), are initiated during the growing season  before buds emerge. Catkins may begin forming in July, while conelets are  formed during a relatively short period of time in August. The number of  flowers produced is apparently related to weather conditions during the  year of initiation. A wet spring and early summer followed by a dry period  in late summer promotes conelet production (27). Catkin production,  however, is favored by abundant rainfall throughout the growing season.  Female strobili are borne most frequently in the upper crown, and male  strobili predominate in the lower crown (26). Late summer rainfall  depresses conelet initiation, probably because vigorous exposed shoots in  the middle and upper crown continue to grow. In the lower crown, where  most catkins are home, shoots stop growing earlier than they do in the  upper crown.

    Since rainfall patterns associated with catkin initiation differ from  those favoring conelets, large crops of male and female flowers do not  necessarily coincide. Ten years of observation did not show any  correlation between size of conelet and pollen crops in longleaf pine.

    Variable but usually heavy annual losses of longleaf pine conelets can  be expected; observed losses have ranged from 65 to 100 percent (2,24,30).  Several agents, alone or in combination, may be responsible. The more  important appear to be insects, bad weather, and insufficient pollen. Over  15 years at one location, cone production was related to pollen density,  to the point of a sufficiency of pollen (2). Further increases in pollen  density had little effect. In some cases, nearly all the losses have been  attributed to insects (24), while in others the more common causes of  conelet losses were not responsible (30). Most conelet losses seem to  occur in the spring, at about the time of pollination, although  substantial losses may also occur in the summer (24). Most of the  spontaneous conelet abortions in longleaf pine may result from excess  ethylene production by foliage and shoots. A foliar spray with  anti-ethylene compounds soon after anthesis has reduced conelet abortion  by half, doubling seed yields (18).

    Catkin buds normally emerge in November, then remain dormant for about a  month before growth resumes. Conelet buds emerge in January or February.  The rate of development of both conelets and catkins thereafter is almost  entirely dependent on ambient temperature. Catkins are purple from the  time they emerge from the buds until they shed their pollen. Upon emerging  from the bud, conelets are red until they are pollinated, after which they  gradually fade to a yellowish green. Most mature catkins range from 3 to 5  cm (1.2 to 2.0 in) in length.

    The average date of peak pollen shed and conelet receptivity may range  from late February in the southern part of longleaf pines' range to early  April toward the northern limits. Most locations may experience flowering  dates close to these extremes. The date of peak pollen shed and conelet  receptivity coincides on individual longleaf pine trees but can vary  considerably among trees in a stand. Some trees are consistently early and  others late in time of flowering, although the differences vary from year  to year, depending on air temperatures before and during the flowering  period (5). Over 22 years of observation, the time required for shedding  80 percent of all pollen in a longleaf pine stand ranged from 5 to 21 days  and averaged 13 (5).

    Pollination takes place in the late winter or spring, but fertilization  does not occur until the following spring. At this time conelets are  growing rapidly, increasing in length from about 2.5 cm (1 in) in February  to about 18 cm (7 in) by May or June (16). Mature cones range in length  from 10 to 25 cm (4 to 10 in). Cones reach maturity between mid-September  and mid-October of their second year. Cones, as they become ripe, change  color from green to dull brown, although cones may be ripe before the  color change (26). The specific gravity of ripe cones ranges from 0.80 to  0.89. Ripeness can be tested by flotation in SAE 20 motor oil; ripe cones  will float but those not yet ripe will sink (26).

Longleaf pine is a high quality timber tree,  well suited to a whole range of products-poles, piling, posts, sawlogs,  plywood, pulpwood, and naval stores. Longleaf naturally prunes itself  well. Most stems are well formed, straight, and largely free of branches.  The species almost always has higher stemwood specific gravities and  produces more dry wood per unit volume than either loblolly or slash pine  (28). Intense exploitation since colonial days, plus lack of planned   regeneration, contributed to the decline of longleaf pine forests that  continues to this day. Once height growth has begun, the species can grow  as well as the other major southern pines on many sites originally  occupied by longleaf, and often exceeds them in growth.

    The critical element in the growth of longleaf pine stands is the  duration of the grass stage. About 70 percent of the variation among  plantations in the form of height-over-age curves was related to the  condition of the planting site: early height growth on unprepared cutover  sites was much slower than on old fields and mechanically prepared cutover  sites (6).

    Reduction of competing ground cover in grass stage seedling stands can  have a large impact on growth and future volume yields. One study (25)  observed the effects of a single aerial application of 2,4,5-T to stands  of 1-year-old longleaf seedlings. Twenty years later, treated stands had  significantly greater tree diameter (10 percent), height (17 percent), and  total volume per unit area (32 percent) than adjacent untreated stands,  although there was no difference in the number of trees per unit area.  Treated stands averaged 83.5 m³/ha (1,193 ft³/acre) total  inside-bark (i.b.) volume, compared to 63.2 m³/ha (904 ft³/acre)  for untreated stands.

    Longleaf pine growth and yield predictions have been published for  periodically thinned even-aged natural stands (15) and also for unthinned  plantations in the west Gulf region (22). Predicted total volume (i.b.)  yields for two common site index classes are given in table 1. The  merchantable proportion of total volume ranges from 78 to 86 percent at  age 20, to 97 to 98 percent at age 40. The peak in periodic annual  increment is reached between ages 20 and 30.

    Table 1- Predicted total volume yields inside bark for  even-aged natural stands of longleaf pine            Site index at base age  50 years              Stand in age in years¹   
Basal area   
21.3 m or 70 ft   
24.4 m or 80 ft              m²/ha  m³/ha  m³/ha      20  13.8    61    71      25  20.0  110  128      30  25.5  160  187      35  29.6  207  241      40  33.1  248  289        ft²/acre  ft³/acre  ft³/acre      20    60     874  1,019      25    87  1,572  1,832      30  111  2,287  2,666      35  129  2,954  3,443      40  144  3,549  4,137      ¹Determined from  ring counts taken at 1.2 m (4 ft), plus 7 years.        The optimum stand density to maintain by periodic thinning varies by  site and management goals. A rather broad range of stand densities, above  a basal area of about 13.8 m²/ha (60 ft²/acre), produces near  maximum periodic volume growth (13). Lower densities concentrate growth on  fewer trees. Longleaf responds well to release provided by thinning if the  released trees have crowns equal to at least one-third to one-half of  total tree height. Small-crowned intermediate or suppressed trees do not  respond promptly to release. Thinning should be from below to release  well-formed dominant and codominant trees.

    Present indications are that longleaf pine plantations should produce  volume growth similar to natural stands if other factors are equal. To the  extent that plantations have had better competition control, with  consequent acceleration of early growth, a particular volume yield should  be reached at an earlier age in plantations than in natural stands.

Roots stabilize trees against wind: longleaf pine
 

Roots of longleaf pine protect from strong winds by forming both large anchoring taproots and a widespread lateral root system.

   
  "The damage resistance of longleaf pine could be related to firm anchorage provided by the large taproot and widespread lateral root system. Our excavations of longleaf pine root systems (Baruch Forest Science Institute, pers. comm.) indicated that longleaf pine taproots extended two meters vertically in the soil and the lateral root system extended up to six meters horizontally from the taproot." (Gresham et al. 1991:425)


"While no systematic study has yet been done, at least four distinct schemes seem to be used to keep roots and soil in decent contiguity. Combinations of more than a single scheme certainly occur, and a given tree may use different schemes or a varying mix of several as it grows from a sapling. (Mattheck [1991] considers some aspects of the tree's problem; Ennos and Fitter [1992] provide information on anchorage in small plants or very young trees; Ennos [2000] gives a good general view of the situation.)...

"An alternative scheme capitalizes on little more than the ability of soil to withstand compressive force. If the trunk is continued downward beneath the soil as a stiff taproot, and if ramifying lateral roots near the soil's surface fix the location of the tree, then pushing the trunk in one direction will push the taproot in the other (Edelin and Atger 1994). Soil, especially when beneath a layer of superficial roots, ought to resist this sideways push quite well; the scheme, which we might just call 'taprooting' is shown in figure 21.3c. Taprooting depends on good resistance of the taproot to bending as a cantilever--a high level of flexural stiffness--as is sufficient broadside area to push against so as not to slip sideways through soil. (Additional substantial vertical 'striker' roots, according to Perry [1982] and Crook and Ennos [1996], may supplement the mechanical role of taproots.)

"A tree that uses the scheme without a healthy taproot is crippled. In over 25 years only one of over seventy loblolly pines (Pinus taeda) around my house has blown over with less than really severe provocation; that one had a rotted taproot. (Taproots normally break when a tree uproots, so they're easily overlooked.) My casual observations of several excavated pines suggest that taproots may develop noncylindrical cross sections in response to wind from a prevailing direction. But when poking around the bases of large uprooted Douglas firs, I was struck by the small size of the taproot breakage points. Of the schemes here, the relative importance of taprooting is the least certain; the best documentation of its role comes from work on larch, by Crook and Ennos (1996)." (Vogel 2003:431,433)
  Learn more about this functional adaptation.

Population Differences    Longleaf pine is a highly variable species, and a considerable  proportion of this variation is genetic. Considering the economically  important traits, longleaf pines have as much or more genetic variation  than other southern pines.

    Variation among individual trees is greater than that among stands or  among geographically diverse seed sources (23,28). Nevertheless, the  diversity of environments throughout the longleaf range has promoted the  development of genetic variation among populations. According to rangewide  provenance tests, trees from coastal areas usually outgrow those from  inland areas at all but the coldest locations. Trees originating from the  central Gulf Coast should be more productive than trees from other sources  on most coastal plain longleaf sites from Georgia and north Florida west  to east central Louisiana (28). Elsewhere, local seed sources may be  safest to use until more information is available.

    Hybrids    The major southern pines, as well as some minor species, are closely  related and have overlapping ranges. Natural hybridization has contributed  to genetic diversity among trees and populations. Natural hybridization is  common between longleaf and loblolly pine, producing the Sonderegger pine  (P. x sondereggeri H. H. Chapm.). This is the only named  southern pine hybrid. Throughout much of the longleaf pine range, the  flowering of longleaf and loblolly pines overlaps in most years so there  is no phenological barrier to natural crossing. Natural hybridization  between longleaf and slash pine is unlikely, based on differences between  the species in dormancy and heat requirements for flowering (5).

    Artificial crosses between longleaf pine and both loblolly and slash  pines can be achieved easily. Crosses between longleaf and shortleaf pine  have not been found in nature but have been produced artificially. There  are no reported successful crosses of longleaf pine with any other pine  species (28).

The following is a representative barcode sequence, the centroid of all available sequences for this species.


No available public DNA sequences.

Download FASTA File

Barcode of Life Data Systems (BOLDS) Stats
Public Records: 5
Specimens with Barcodes: 13
Species With Barcodes: 1

More info for the term: natural

Only a few old-growth stands of longleaf pine remain in the southeastern United States [43]. Although longleaf pine is not an endangered species, many endangered plant and animal species live in longleaf pine communities. Longleaf pine communities are ranked as threatened by the Texas Natural Heritage Program [9].

Year Assessed

• Needs updating

Assessor/s

Reviewer/s

Rounded Global Status Rank: G5 - Secure

United States

Rounded National Status Rank: N5 - Secure

Please consult the PLANTS Web site and your State Department of Natural Resources for this plant’s current status (e.g. threatened or endangered species, state noxious status, and wetland indicator values).

Major Threats

The main disease of longleaf pine is brown-spot needle blight (Scirrhia acicola). Other diseases include pitch canker, annosus root rot, and cone rust. Insects that attack longleaf pine include black turpentine beetle, bark beetles, and seed bugs.

More info for the terms: density, selection, tree

Longleaf pine communities are estimated to have once covered 59 to 87
million acres (24-35 million ha); now only 5 to 10 million acres (2-4
million ha) remain. Of that remaining, most is second growth and
in poor condition [40,41]. Because of its timber value and because longleaf
pine communities house many endangered plant and animal species, forest
managers are attempting to regenerate more longleaf pine communities.

Natural regeneration of longleaf pine is difficult because of poor seed
production, heavy seed predation by animals, poor seedling survival, and
slow seedling growth. Longleaf pine is best managed with even-aged
silviculture using a three-cut shelterwood system [2,5,18,25]. The
preparatory cut, 10 years before expected seed crop, should leave a
basal area of 60 to 70 square feet per acre (13.8-16.1 sq m/ha). The
remaining trees will develop larger crowns and increase seed production.
The seed cut, 5 years before the expected seed crop, should leave a
basal area of 30 square feet per acre (6.9 sq m/ha). The seedbed should
be prepared, usually with fire, when a good seed crop is evident from
large numbers of conelets. Seed trees should be removed 1 to 2 years
after seedlings are established and before height growth has been
initiated [5,25].
The group selection method can be used to naturally regenerate
uneven-aged stands. Up to 2 acres (0.8 ha) of trees should be cut so
discernible openings are created [2].
Methods for artificial regeneration of longleaf pine are detailed in
Rounsaville 1989 [45].
Disease and insects: Longleaf pine is highly resistant to most diseases
and insects that infect other southern pines. The main disease of
longleaf pine is brown-spot needle blight (Scirrhia acicola).
Defoliation suppresses and eventually kills grass-stage seedlings [7].
Infection of seedlings is less severe under a pine overstory than in the
open [4]. About 20 percent of seedlings are resistant to brown-spot
needle blight [17]. (See Fire Management).
Other diseases include pitch canker (Fusarium moniliforme var.
subglutinans), annosus root rot (Heterobasidion annosum), and cone rust
(Cronartium strobilinum). Insects that attack longleaf pine include
black turpentine beetle (Dendroctonus terebrans), bark beetles (Ips
spp.), and seed bugs (Tetyra bipunctata and Leptoglossus corculus),
which can decimate a seed crop [7].
Predation: Despite fall germination, which minimizes the time seed lies
on the forest floor, predation by birds and small mammals can decimate a
seed crop [18].
Weather: Because of the fall germination, low winter temperatures can
damage cotyledons. March frosts can destroy flowers. Hurricanes,
tornadoes, and lightning cause local damage [7,18].
Other considerations: Moderate cattle grazing has no effect on longleaf
survival, but heavy grazing reduces young tree density by 20 percent
[54]. Hogs significantly reduce longleaf pine establishment and can
cause crop failure [30].

No cultivars are currently recommended. Seeds and seedlings are commercially available from woody plant seed companies. The number of seeds per pound ranges from 3,000 to 7,000.

Longleaf pine is intolerant to both shade and competition. With frequent fire, uneven-aged pure stands form park-like savannahs. Because longleaf pine regenerates in openings created by dead trees, small clusters of trees of the same age are dispersed throughout the stand. In the absence of frequent fire, the species is replaced by hardwoods and other southern pines; this hastens the decline of mature longleaf pine. Lightning ignited fires are pivotal to perpetuation of longleaf pine on a site indefinitely. Excessive grazing reduces young tree density.

Longleaf pine's needles are used for mulch. Resin is used in the naval stores industry for gum turpentine and rosin production [7].

Wood Products: Longleaf pine, a valued timber species, has clear, straight wood with few defects [18]. It was used extensively in the past for timber and ship building. Most virgin stands have now been harvested. Because longleaf pine is not as easy to regenerate as other southern pine timber species, it is not used as extensively as it once was. Longleaf pine's highly desirable wood, however, has stimulated efforts to regenerate it [7,18].

Longleaf pine forests provide excellent habitat for bobwhite quail, white-tailed deer, wild turkey, and fox squirrel. Sixty-eight species of birds utilize longleaf pine forests [45]. Birds, and mice, squirrels, and other small mammals eat the large seeds. Ants eat germinating seeds, and razorback hogs eat the roots of seedlings [7,54]. Old-growth longleaf pine stands provide nesting habitat for the endangered red-cockaded woodpecker [16].

Nutritional value: Longleaf pine seed is more than 25 percent protein and more than 0.05 percent phosphorus [47].

Longleaf pine is recommended for reforestation of dry, infertile, deep sands in the southeastern United States. Most of these sites were formerly longleaf pine forests but were invaded by scrub oaks (Quercus spp.) after timber harvesting [48]. Longleaf pine is of limited use for rehabilitation of mine spoils in Alabama [50].

Longleaf pine is used for a broad range of forest products. Even old  lightered stumps (those having resin-soaked heartwood characteristic of  old trees) are pulled out and the stumpwood destructively distilled for  chemicals. Longleaf "pine straw" is in demand for use as a  mulch, so fresh needle litter is sometimes collected, baled, and sold. The  longleaf pine forest, if regularly burned, has a parklike appearance with  an understory dominated by grasses and forbs; an excellent habitat for  game, especially quail, and quail hunting has long been associated with  this timber type. The understory produces a substantial amount of high  quality forage for both cattle and deer (17,31). Mature longleaf stands  also provide the most desirable habitat for the red-cockaded woodpecker.

Erosion Control: Longleaf pine is a highly recommended species for reforestation of dry, infertile, deep sands in the southeastern U.S. It is has limited potential for rehabilitation of mine spoils.

Wildlife: Birds and small mammals eat the large seeds, ants feed on germinating seeds, and razorback hogs eat the roots of seedlings. This species provides excellent habitat for bobwhite quail, white-tailed deer, wild turkey, and fox squirrel. Old-growth stands provide nesting habitat for the red-cockaded woodpecker.

Timber: The wood is often clear, straight, and with few defects and used for timber and ship building.

Recreation and Beautification: Longleaf pine needles are used for mulch. Resin is used in the naval stores industry for gum turpentine and rosin production.

Pinus palustris is fire successional, with a deep taproot and a definite grass stage. It is a valued species for lumber and pulpwood and was once important for naval stores (e.g., turpentine, pine oil, tar, pitch). It is fast disappearing over much of its natural range, partly through overharvesting but especially because of difficulties in adapting it to current plantation and management techniques. 

 Longleaf pine ( Pinus palustris ) is the state tree of North Carolina.