Pinus strobus, the Eastern White Pine, is characterized by fascicles of 5 fine needles with a nonpersistent bundle sheath, and relatively soft, unarmed, elongate seed cones whose scales are spread at maturity. The native range of eastern white pine stretches from southeastern Manitoba to Newfoundland in Canada and from Minnesota and Iowa eastward to Maine and Pennsylvania, with a southward Appalachian extension to Tennessee and Georgia and isolated occurrences in western Kentucky, Illinois, and Indiana. The species also has become naturalized from plantings, both within its historical range and elsewhere, including portions of Europe, Asia, New Zealand, and Australia. A related taxon in portions of southern Mexico and Guatemala is sometimes treated as Pinus strobus var. chiapensis, but more often as a distinct species, Pinus chiapensis.
Natural stands of Pinus strobus occur in a variety of habitats, ranging from dune forests to bogs and mixed conifer/hardwood forests. The species also colonizes old fields and other former agricultural lands that are reverting back to forests. It has been planted extensively in plantations and is also used to revegetate mine spoils. The species also is cultivated commonly as a shade and ornamental tree
Eastern White Pine is an important timber tree for the production of softwood lumber. The wood is used for construction, cabinetry and furniture-making, handcrafts, and various other woodworking. Native American tribes used it extensively for various medicinal properties and it is an important food source for wildlife. The long history of cultivation has led to the development of numerous cultivars and forms. The species is affected by the exotic white pine blister rust Cronartium ribicola, an important pathogen of timber trees in the white pine group in temperate North America.
G. W. Wendel and H. Clay Smith
Eastern white pine (Pinus strobus), also called northern white pine, is one of the most valuable trees in eastern North America. Before the arrival of white men, virgin stands contained an estimated 3.4 billion m³ (600 billion fbm) of lumber. By the late 1800's most of those vast stands had been logged. Because it is among the more rapid growing northern forest conifers, it is an excellent tree for reforestation projects, landscaping, and Christmas trees and has the distinction of having been one of the more widely planted American trees.
White pine was a favorite tree of naturalist/author Henry David Thoreau. According to Ray Angelo’s botanical index to Thoreau’s writings, white pine received more mention than almost any other tree. Climbing a tall specimen of white pine altered Thoreau’s view of the world: “We hug the earth — how rarely we mount! Methinks we might elevate ourselves a little more. We might climb a tree at least. I found my account in climbing a tree once. It was a tall white pine on the top of a hill, and though I got well pitched I was well payed for it, for I discovered new mountains in the horizon which I had never seen before, — so much more of the earth and the heavens. I might have walked about the foot of the tree for three score years and ten, and yet I certainly should never have seen them.” Henry David Thoreau, Walking, an essay first delivered on 23 April 1851 at the Concord Lyceum, published posthumously in The Atlantic Monthly, 9 June 1862, pp. 657–674.
Pinus strobus L, eastern white pine, is the largest conifer of the eastern and upper Midwest forests, reaching 150 feet in height and up to 40 inches in diameter. In dense stands, trees produce tall, cylindrical stems with pyramidal shaped crowns, characterized by distinctive, plate like branching, especially noticeable as the trees become older. On young growth, the bark remains rather thin, smooth, and greenish-brown in color. On older trees the bark becomes deeply fissured and dark grayish-brown in color. Its evergreen needles are in clusters of 5, soft, flexible, 2 1/2 to 5 inches long, and bluish-green in appearance. Its cones are about 4 to 8 inches long and 1 inch thick. These remain attached for 1 to several months after ripening in the autumn of the second season.
Pinus strobusL., Species Plantarum 2: 1001
Linnaeus, C. 1753. Species Plantarum : Exhibentes Plantas Rite Cognitas, Ad Genera Relatas, cum Differentiis Specificis, Nominibus Trivialibus, Synonymis Selectis, Locis Natalibus, Secundum Systema Sexuale Digestas, vol. 2. Impensis Laurentii Salvii, Stockholm.
Distribution and adaptation
Eastern white pine grows on a variety of soils ranging from light, sandy to heavy textured soils. White pine ranges across southern Canada from Manitoba to Newfoundland, throughout the northern and eastern states from Minnesota and northern Iowa to the Atlantic coast, and southward along the Appalachian mountains to northern Georgia and Alabama.
For a current distribution map, please consult the Plant Profile page for this species on the PLANTS Website.
Range and Habitat in Illinois
Regularity: Regularly occurring
Regularity: Regularly occurring
Occurrence in North America
MI MN NH NJ NY NC OH PA RI SC
TN VT VA WV WI MB NB NF ON PE
southeastern Manitoba and south to the Great Lake States, along the
Atlantic seaboard to New Jersey, and in the Appalachian Mountains to
northern Georgia. It also occurs in Iowa, western Kentucky, western
Tennessee, and Delaware [31,68].
- The native range of eastern white pine.
rapidly and in 40 years can be 60 feet (18.3 m) tall and 8 to 10 inches
(20-25 cm) in d.b.h. . Individuals of 150 feet (46 m) and 40 inches
(102 cm) in d.b.h. were common in virgin forests. Eastern white pine
commonly reaches 200 years of age and may exceed 450 years . In
closed stands, boles are free of branches for over two-thirds of their
length. Needles are 2.5 to 5.0 inches (6-13 cm) long, and the winged
seeds are about 0.8 inches (2 cm) long. The roots are widespreading and
moderately deep without a distinct taproot .
Habitat and Ecology
Range and Habitat in Illinois
Eastern white pine occurs on a variety of sites along the full moisture
gradient from wet bogs and moist streambottoms to xeric sand plains and
rocky ridges [7,67]. In Maine and New Brunswick, eastern white pine
occurs in well0drained, raised bogs ; in Michigan, it occurs on sand
dunes . In the southern Appalachian Mountains and in Pennsylvania,
pure stands mainly occur on northerly aspects, in coves, and on
streambottoms . Eastern white pine is common on the east shore of
lakes where blowdowns create openings for regeneration .
In New England, eastern white pine usually occurs between sea level and
2,000 feet (610 m) in elevation; on Catamount Mountain in the Adirondack
Mountains of New York, it occurs up to 3,168 feet (966 m). In the
southern Appalachian Mountains, it occurs between 1,200 and 3,500 feet
(370-1,070 m) [11,28]
Eastern white pine grows on nearly all soil types within its range. It
is most competitive on fairly infertile sandy soils, such as
well-drained outwash soils. On clay or poorly drained soils, eastern
white pine occurs only as individuals or in small groups. It grows on
fine sandy loams and silty loams on disturbed sites if there is little
hardwood competition .
Eastern white pine is the characteristic old-field species in New
England. Nearly pure stands develop on old fields where seed is ample
and sod is intact . In the Hudson River valley, eastern white pine
dominates the finer textured, less rocky old-field sites, whereas oak
communities dominated the coarser textured, rockier sites .
Tree associates of eastern white pine not mentioned in Distribution and
Occurrence include sweet birch (Betula lenta), bigtooth aspen (Populus
grandidentata), quaking aspen (P. tremuloides), black cherry (Prunus
serotina), and black oak (Quercus velutina) .
Understory species are scarce in pure stands of eastern white pine. On
dry sites, associates include blueberries (Vaccinium spp.), wintergreen
(Gaultheria procumbens), dwarf bush-honeysuckle (Diervilla lonicera),
sweetfern (Comptonia peregrina), bracken fern (Pteridium aquilinum),
clubmosses (Lycopodium spp,), and broomsedge (Andropogon virginicus).
On moist, rich sites associates include wood sorrel (Oxalis spp.),
partridgeberry (Mitchella repens), wild sarsaparilla (Aralia
nudicaulis), jack-in-the-pulpit (Arisaema triphyllum), and hay-scented
fern (Dennstaedtia punctilobula). Other associates include bigleaf
aster (Aster macrophyllus), Canada mayflower (Maianthemum canadense),
and bunchberry (Cornus canadensis) [11,41,25].
Key Plant Community Associations
Eastern white pine frequently dominates or codominates xeric northern
pine forests [7,40]. In mixed hardwood forests, it often occurs as a
scattered dominant tree towering above the surrounding hardwoods
Publications listing eastern white pine as dominant or codominant are as
A multivariate analysis of forest communities in the western Great Smoky
Mountains National Park 
The vegetation of Wisconsin 
The principal plant associations of the Saint Lawrence Valley 
Field guide: forest habitat types of northern Wisconsin 
Plant communities of Voyageurs National Park, Minnesota, U.S.A. 
A classification of the deciduous forest of eastern North America 
Virgin plant communities of the Boundary Waters Canoe Area 
Forest associations in the Harvard Forest 
Plant community pattern analysis: a cartographic approach applied in
the Lac des Deux-Montagnes area (Quebec) 
Habitat: Cover Types
This species is known to occur in association with the following cover types (as classified by the Society of American Foresters):
1 Jack pine
5 Balsam fir
14 Northern pin oak
15 Red pine
18 Paper birch
19 Gray birch - red maple
20 White pine - northern red oak - red maple
21 Eastern white pine
22 White pine - hemlock
23 Eastern hemlock
24 Hemlock - yellow birch
25 Sugar maple - beech - yellow birch
26 Sugar maple - basswood
27 Sugar maple
30 Red spruce - yellow birch
31 Red spruce - sugar maple - beech
32 Red spruce
33 Red spruce - balsam fir
35 Paper birch - red spruce - balsam fir
37 Northern white-cedar
39 Black ash - American elm - red maple
43 Bear oak
44 Chestnut oak
45 Pitch pine
51 White pine - chestnut oak
53 White oak
59 Yellow-poplar - white oak - northern red oak
60 Beech - sugar maple
108 Red maple
Habitat: Plant Associations
This species is known to occur in association with the following plant community types (as classified by Küchler 1964):
K093 Great Lakes spruce - fir forest
K095 Great Lakes pine forest
K096 Northeastern spruce - fir forest
K097 Southeastern spruce - fir forest
K099 Maple - basswood forest
K100 Oak - hickory forest
K101 Elm - ash forest
K102 Beech - maple forest
K104 Appalachian oak forest
K106 Northern hardwoods
K107 Northern hardwoods - fir forest
K108 Northern hardwoods - spruce forest
K110 Northeastern oak - pine forest
K111 Oak - hickory - pine forest
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):
FRES10 White - red - jack pine
FRES11 Spruce - fir
FRES13 Loblolly - shortleaf pine
FRES15 Oak - hickory
FRES17 Elm - ash - cottonwood
FRES18 Maple - beech - birch
FRES19 Aspen - birch
Soils and Topography
In northern Minnesota, Eutroboralfs, Haplorthods, Udipsamments, and Hapludalfs are among the most common of the great groups (2). They are similar to the soils of New England and are more or less freely drained and have developed on glacial outwash or till material.
Dystrochrepts, Fragiodults, and Normudults are the major great groups occupied by white pine in the central Appalachian Mountains (45). These soils are weathered from acid shales and sandstones, either in place (residual soils), deposited on lower slopes (colluvial material), or along stream terraces (alluvial material). The soils are generally well drained and have a coarse loamy to a fine loamy texture.
Soils within the range of white pine are derived from granites, gneisses, schists, and sandstones, and less commonly from phyllites, slates, shales, and limestones. In the northern part of the Lake States and southern Canada, white pine is usually confined to soils derived from basalts, gabbro, diabase, and granites (70). Most of the area was covered by the Wisconsin glaciation so the soils are young and have weakly developed profiles (67). In New Hampshire, white pine is found on granite-derived soils and on metamorphic crystalline schists (42). From central Pennsylvania south and in southwestern Wisconsin, the soils are much older, generally are finer textured, and have well developed profiles.
White pine grows on nearly all the soils within its range (71), but generally competes best on well drained sandy soils of low to medium site quality. These soils permit fair growth of white pine but not hardwoods. On these sandy sites, white pine regenerates naturally, competes easily, and can be managed most effectively and economically (40,47). On medium-textured soils (sandy loams), it will outproduce most other native commercial species in both volume and value (47). White pine also grows on fine sandy loams and silt-loam soils with either good or impeded drainage when there is no hardwood competition during the establishment period-as on old fields and pastures, bums, and blowdowns. It has been found on clay soils and on poorly drained or very poorly drained soils with surface mounds. It can be very productive on these sites but usually occurs only as individual trees or in small groups (47). This pine should not be planted in heavy clay soils. Poorly drained bottom land sites and upland depressions are also poor choices for planting (6).
At various places within white pine's range, site quality has been related to combinations of soil and topographic characteristics such as texture and thickness of the A and B horizons, depth and permeability of the underlying rock or pan, depth to the water table, natural drainage class, topographic position, slope percent, and aspect. In the unglaciated regions of Ohio and central Indiana, site quality for white pine increases as the soil becomes coarser in texture and declines as the moisture equivalent and wilting percentage increase in the A and B horizons (71). But thickness of the A horizon had the greatest influence on rate of growth.
In Massachusetts white pine site quality increased with the increase in silt and clay fraction of the A horizon, with higher pH value of the B or C horizon, with increased stone and gravel fraction greater than 2 mm (0.08 in) in the A horizon, with greater nitrogen content in the A horizon, and with higher percent organic matter in the B horizon (46). In general, the higher site indices are associated with the poor soil drainage classes. On reclaimed soils, white pine should not be planted on sites with a pH of less than 4.0 (6).
In New Hampshire, the average height of dominant and codominant trees increased as the soil tended to be less well drained (7,71). Site productivity in Maine showed the following responses: increase with a reduction in soil drainage; increase with pH increases in surface mineral horizons; decrease with increased content of stones larger than 0.6 cm. (0.25 in) in the C horizon, but increase with the contents of stones in surface horizon; increase with thickness of the A horizon; increase with soil depth to a bulk density of 1.40 or greater; increase with increasing availability of soil moisture in the upper 76 cm (30 in) of soil (59).
In the southern part of its range, white pine grows best on soils along rivers and streams and grows somewhat more slowly on well drained sites (22). The growth of white pine in plantations in eastern Tennessee was found to decrease with increased plasticity of the B horizon (71).
Pine often grows better than some of its associates on poor soils or sites, such as in northeastern Iowa where white pine was 8 site index points better than oaks on the poor soils (71). In a comparison of site index and growth of 10 species in the southern Appalachians, white pine exceeded all species in growth, except on the best sites, where yellow-poplar outranked it in height only. In New England, white pine frequently pioneers on abandoned agricultural land but only on the well-drained to excessively drained deposits-outwash, sandy tills, and shallow bedrock. White pine may form part of the climax (edaphic) on the driest of these materials or may alternate with oak (42).
In New England and New York, white pine generally grows at elevations between sea level and 460 m (1,500 ft), occasionally higher. In Pennsylvania, the elevation ranges from 150 to 610 m (500 to 2,000 ft) (71). In the southern Appalachians, white pine grows in a band along the mountains between 370 and 1070 m (1,200 and 3,500 ft) above sea level, occasionally reaching 1220 m (4,000 ft). In Pennsylvania and the southern Appalachians, most white pine is found on northerly aspects, in coves, and on stream bottoms. Elsewhere, aspect seldom restricts its occurrence (71).
Annual precipitation ranges from about 510 mm (20 in) in northern Minnesota to about 2030 mm (80 in) in northwestern Georgia. In the area surrounding the Great Lakes, about two-thirds of the precipitation occurs during the warm season, April to September. Elsewhere, half of the precipitation occurs during the warm season. The length of the growing season ranges from 90 to 180 days.
Throughout the range of white pine, precipitation is about 1 to 1.5 times the evaporation from shaded free water surfaces (71). Annual potential evapo- transpiration is between 430 and 710 mm. (17 and 28 in), of which 56 to 68 percent occurs in the warm season. There is a moisture surplus in all seasons.
Average depth of frost penetration ranges from about 25 cm (10 in) in the southern Appalachians to more than 178 cm (70 in) in parts of central and northern Minnesota. Average annual snowfall ranges from 13 cm (5 in) in northern Georgia to more than 254 cm (100 in) in New England and southern Canada (51).
Habitat & Distribution
Habitat & Distribution
Seedlings of white pine are grown in nursery beds for field planting. They may either be left in the nursery for 2 to 3 years and directly planted into the field, or they may be transplanted after the second year and left in a transplant bed for 1 or 2 years before field plantings. This will produce a seedling approximately 12 to 16 inches in height with 1/4 to 1/2 inch caliper. Field establishment of seedlings is accomplished with tree planting procedures, using machine transplanters or hand planting.
communal larva of Acantholyda erythrocephala feeds from web on needles of Pinus strobus
Other: major host/prey
Foodplant / pathogen
Armillaria mellea s.l. infects and damages Pinus strobus
Foodplant / pathogen
subcortical pycnium of Cronartium ribicola infects and damages stem of Pinus strobus
Remarks: season: 3-6
Other: major host/prey
Foodplant / saprobe
scattered, immersed, up to 2mm diam. stroma of Cytospora coelomycetous anamorph of Cytospora pini is saprobic on dead bark of Pinus strobus
In Great Britain and/or Ireland:
Foodplant / feeds on
gregarious, subepidermal then erumpent through cleft epidermis, dull black pycnidium of Diplodina coelomycetous anamorph of Diplodina strobi feeds on needle of Pinus strobus
Remarks: season: 1-5
Foodplant / pathogen
Brunchorstia anamorph of Gremmeniella abietina infects and damages live twig of Pinus strobus
Remarks: Other: uncertain
Fungus / saprobe
subepidermal, then exposed apothecium of Meloderma desmazieri is saprobic on leaf of Pinus strobus
Foodplant / saprobe
hysterothecium of Mytilinidion scolecosporum is saprobic on wood of Pinus strobus
Other: major host/prey
Foodplant / saprobe
stromatic, in large groups perithecium of Nectria fuckeliana is saprobic on dead twig of Pinus strobus
Remarks: season: 3-5, 9-12
Foodplant / saprobe
Cryptosporiopsis anamorph of Pezicula livida is saprobic on dead, fallen branch of Pinus strobus
Foodplant / sap sucker
Pineus strobi sucks sap of live shoot of Pinus strobus
Remarks: season: 1-12
Foodplant / saprobe
immersed, becoming erumpeny conidioma of Strasseria coelomycetous anamorph of Strasseria geniculata is saprobic on dead twig of Pinus strobus
Remarks: season: 1-5
Foodplant / mycorrhiza / ectomycorrhiza
fruitbody of Suillus placidus is ectomycorrhizal with live root of Pinus strobus
Foodplant / mycorrhiza / ectomycorrhiza
fruitbody of Thelephora terrestris is ectomycorrhizal with live root of Pinus strobus
Remarks: captive: in captivity, culture, or experimentally induced
Fungus / saprobe
immersed apothecium of Therrya pini is saprobic on brittle, dead, attached, lacking needles branch (small) of Pinus strobus
Remarks: season: 2-7
Foodplant / saprobe
immersed, grouped perithecium of Valsa pini is saprobic on dead twig of Pinus strobus
Remarks: season: 11-2
Associated Forest Cover
1 Jack Pine
5 Balsam Fir
14 Northern Pin Oak
18 Paper Birch
19 Gray Birch-Red Maple
23 Eastern Hemlock
24 Hemlock-Yellow Birch
25 Sugar Maple-Beech-Yellow Birch
26 Sugar Maple-Basswood
30 Red Spruce-Yellow Birch
31 Red Spruce-Sugar Maple-Beech
32 Red Spruce
33 Red Spruce-Balsam Fir
35 Paper Birch-Red Spruce-Balsam Fir
37 Northern White-Cedar
39 Black Ash-American Elm-Red Maple
44 Chestnut Oak
45 Pitch Pine
53 White Oak
59 Yellow-Poplar-White Oak-Northern Red Oak
60 Beech-Sugar Maple
108 Red Maple
White pine also grows with pitch pine (Pinus rigida), jack pine (P. banksiana), shortleaf pine (P. echinata), sweet birch (Betula lenta), bigtooth aspen (Populus grandidentata), quaking aspen (P. tremuloides), black cherry (Prunus serotina), black oak (Quercus velutina), white oak (Q. alba), and various hickories (Carya spp.). The ground vegetation in a white pine stand varies greatly, as evidenced by the number of forest cover types in which it is a major or minor component. Beneath pure or nearly pure stands of white pine, understory plants usually are sparse compared to those in the pine-hardwood mixtures (70).
In general, on dry sites the understory vegetation is usually of one or more species of blueberries (Vaccinium spp.), teaberry (Gaultheria procumbens), dwarf bush-honeysuckle (Diervilla lonicera), sweetfern (Comptonia peregrina), bracken (Pteridium aquilinum), clubmoss (Lycopodium spp.), and broomsedge (Andropogon virginicus). The moist, rich sites support a ground vegetation made up principally of several species of woodsorrel (Oxalis), partridgeberry (Mitchella repens), wild sarsaparilla (Aralia nudicaulis), jack-in-the-pulpit (Arisaema spp.), and hay-scented fern (Dennstaedtia punctilobula). Intermediate sites have ground vegetation containing various amounts of the above with dogwood (Cornus spp.) and false lily- of-the -valley (Maianthemum canadense).
Diseases and Parasites
Among other insect enemies are white pine aphid (Cinara strobi), which causes damage to twigs and branches of large trees and sometimes kills small trees; white pine sawfly (Neodiprion pinetum), which feeds on old and new foliage; Zimmerman pine moth (Dioryctria zimmermani); the Allegheny mound ant (Formica exsectoides), which injects formic acid into the tree tissue; pales weevil (Hylobius pales), which feeds on bark of young twigs and seedlings; pine root collar weevil (H. radicis); European pine shoot moth (Rhyacionia buoliana), which feeds on buds and twigs causing crooked trunks and branches; eastern pine shoot borer (Eucosma gloriola), which attacks terminal needle sheaths, often causing bushiness after repeated attacks; introduced pine sawfly (Diprion similis), which feeds on foliage and may defoliate an entire tree in one season; and white pine cone borer (Eucosma tocullionana), which feeds on white pine cones and is a potentially serious pest (5).
White pine blister rust (Cronartium ribicola) is highly virulent throughout the range of white pine. Trees are susceptible from the seedling stage through maturity. Blister rust can cause high losses both in regeneration and in immature timber stands (71).
Red ring rot caused by Phellinus pini isthe most important heart rot of white pine. The fungus enters through wounds, dead limbs, or tips killed by weevils. Losses are greater in older trees but do not build up rapidly. Haematostereum sanguinolentum, a wound parasite, is probably the third most destructive fungus associated with white pine. It usually enters through pruning wounds (71).
Phaeolus schweinitzii causes one of the most common and destructive root rots. A root rot caused by Heterobasidion annosum is found particularly on white pines growing on poorly aerated soils. Thinnings appear to increase the incidence of this disease (71). Armillaria mellea destroys much of the white pine seedling and sapling reproduction for distances up to 9 m (30 ft) from hardwood stumps. The fungus radiates and girdles pines at the root collar and causes resinosis (33). Other root rots that attack white pine are Inonotus tomentosus and Scytinostroma galactinium. Many fungi invade white pine foliage. The most serious damage is caused by Bifusella linearis, which attacks first-year needles; Scirrhia acicola, which can cause spring shedding of all needles; and Capnodium pini, which causes surface sooty mold on aphid secretions on needles.
Three categories of nursery diseases are pre-emergence and post-emergence damping off, most commonly caused by Rhizoctonia solani, Fusarium spp., Pythium debaryanum, P. ultimum, and Phytophthora cinnamomi; damping off and root collar rot caused by the preceding fungi and Cylindrocladium scoparium and Diplodia pinea; and foliage and succulent stem blights caused by Cylindrocladium scoparium, Diplodia pinea, Phacidium infestans, and Rhizina undulata. In the field, seedlings may be attacked by Armillaria mellea and by most of the fungi observed in the nursery. In 3- to 10-year-old plantations in Pennsylvania, Verticicladiella procera was identified (65).
The bark on exposed roots and the stem in second-growth white pine stands is thin, and fire resistance is low. Losses invariably are heavy after a fire, with mortality continuing for several years. Also, fire injury is probably responsible for introducing disease agents. If fires occurred more frequently than once in 10 years, white pine reproduction might be eliminated (53). Old trees have thicker bark and are at least moderately resistant to fire.
The species is relatively windfirm. if permitted full development, but in dense stands, wind damage may be expected from an occasional severe storm, particularly after a recent partial cutting (71). Wind-deformed trees are subject to later compression failures in the bole. Also, white pine is damaged by deer browsing; ice and snow, which often cause limb and stem breakage; sulfur dioxide in stack gases resulting from large scale burning of coal and oil refining; fluorine gas from brick kilns; atmospheric ozone; and sea-salt spray (11,26,33,58).
Fire Management Considerations
Prescribed fire is used for eastern white pine seedbed preparation. Two
fires conducted in consecutive years are recommended before the first
partial cut of a shelterwood system. A fire conducted after the partial
cut may be too hot because of slash and may cause mortality of the
remaining trees. The first fire should be in the spring before the
understory leaves emerge so that the fire is hot enough to remove most
of the soil surface organic material. A second fire after the leaves
emerge the following year helps reduce competition. A suggested
reasonable fire intensity for preparing a seedbed and controlling
competition is 116 to 173 btu/s/ft (400-600 kW/m). Extreme care must be
taken if prescribed burning stands younger than 80 years old .
Two consecutive annual fires in a 90-year-old eastern white and red pine
stand in Ontario improved the conditions necessary for pine
regeneration. The fires were low in intensity (22 to 23 btu/s/ft [78-79
kW/m]) and did not harm the overstory. The litter layer was consumed,
and the understory changed from one dominated by balsam fir saplings to
one dominated by herbaceous species. However, very little eastern white
pine reproduction occurred in the first 3 postfire years .
The white pine cone beetle larvae spend 9 to 10 months a year in dead
cones on the forest floor. The beetle can be controlled by a
low-severity surface fire in early spring before it emerges .
Broad-scale Impacts of Plant Response to Fire
The following Research Project Summaries provide information on prescribed fire use and postfire response of plant community species, including eastern white pine, that was not available when this species review was originally written:
- Prescribed burning experiments in red and eastern white pine forests of eastern Ontario
- Effects of surface fires in a mixed red and eastern white pine stand in Michigan
- Early postfire response of southern Appalachian Table Mountain-pitch pine stands to prescribed fires in North Carolina and Virginia
Plant Response to Fire
Eastern white pine colonizes burns if a seed source is nearby
A thick organic layer is an unfavorable seedbed because roots of new
seedlings desiccate before reaching mineral soil. The higher the fire
severity, the more organic material is removed. However, severe fire
also consumes seeds and rhizomes and thus reduces the early postfire
herbaceous cover which serves to shelter young seedlings from heat.
Initially, as the amount of postfire shelter is reduced by increasing
fire severity, eastern white pine survival decreases. Eventually,
however, the reduction in organic matter depth is sufficient to
compensate for the lack of shelter and the survival of eastern white
pine increases. Establishment is highest when mineral soil is exposed
Fire wounds provide entry to fungi which cause heart rot in eastern
white pine .
Immediate Effect of Fire
Once eastern white pine reaches 60 feet (18 m) in height and develops
rough bark on the lower bole, it tolerates low-severity fire [32,69].
Large individuals usually survive moderate-severity fires . Fires
of more than moderate severity during the first 50 years may destroy the
entire stand .
Total scorching of foliage typically kills eastern white pine , but
scorching less than 50 percent is usually not lethal [35,61,66]. Two
stands, in which 96 percent of the eastern white and red pines were 9
inches (23 cm) in diameter or larger, were prescribed burned in late
spring (May 31 and June 15). The percent crown scorch was estimated
after the fire and 1-year mortality was assessed. There was no
mortality in trees with less than 46 percent crown scorch. Mortality
was 50 percent in the 81 to 85 percent crown scorch class and 100
percent in trees with more than 96 percent crown scorch .
Many eastern white pine were crown scorched up to 50 percent in a March
prescribed fire ranging in intensity from 30 to 250 btu/s/ft (100-850
kW/m), but all buds emerged later in the spring .
A laboratory study in August in which eastern white pine seedlings were
exposed to different temperature regimes for 4 minutes, demonstrated
even less mortality with high percentages of needle scorch. The
seedlings withstood up to 90 percent needle scorch with only 10 to 20
percent mortality. The author suggests that there may be two lethal
temperatures, one that kills needles and one that kills terminal buds.
Therefore percent needle scorch may not be directly related to
mortality in eastern white pine .
Deep-burning ground fires may cause root injuries that are more serious
than crown injury. Where 75 percent or more of the major surface roots
had been killed or severely damaged by fire, but only a third or less of
the crown was scorched, mortality 3 years after the fire was 100, 60,
and 40 percent for small trees (2 to 6 inches [5-15 cm] in diameter),
medium trees (7 to 11 inches [16-29 cm]), and large trees (greater than
12 inches [30 cm]), respectively. For trees with less than 25 percent
root kill or injury and more than two-thirds of the crown scorched,
mortality for small, medium, and large trees was only 80, 46, and 14
percent, respectively .
Heated air at 144 degrees Fahrenheit (62 deg C) applied for 1 minute
killed 50 percent of 5-year-old eastern white pine seedlings that
averaged 16 inches (40 cm) in height, 0.2 inch (0.5 cm) butt diameter,
and less than 0.04 inch (0.1 cm) in bark thickness .
Tree without adventitious-bud root crown
Initial-offsite colonizer (off-site, initial community)
Secondary colonizer - on-site seed
Secondary colonizer - off-site seed
Eastern white pine is moderately fire resistant. Mature trees survive
most surface fires because they have thick bark, branch-free boles, and
a moderately deep rooting habit. Younger trees are not as fire
resistant . The needles have relatively low resin content so are
not highly flammable .
Forests dominated or codominated by eastern white pine have different
FIRE REGIMES depending on site and associated species. The natural fire
regime in eastern white pine-red pine forests consists of nonlethal
surface fires at 5- to 50-year intervals punctuated by severe
stand-replacing fires at longer intervals. In the Boundary Waters Canoe
Area in Minnesota, low-severity fire intervals averaged 36 years, and
severe fire intervals averaged 160 years. Eastern white pine forests
growing on more mesic sites with a substantial shade-tolerant component
probably undergo only one fire every 150 to 350 years [16,17]. Some
large individuals survive or escape severe fires and serve as seed
sources for a new stand. Severe fire creates large open areas with ash
or mineral seedbeds and reduces competition, good conditions for eastern
white pine regeneration [19,65].
The typical fuel type under eastern white and red pine stands is an
organic layer 2 to 4 inches (5-10 cm) deep, a continuous needle layer, a
moderate forb and shrub layer, and a moderately dense understory.
Ground fires spread slowly in this fuel type. Dry, windy conditions are
required for fires to crown and have a high rate of spread .
More info for the terms: climax, surface fire
Facultative Seral Species
Eastern white pine is intermediate in shade tolerance  and is present
in all successional stages. It is a pioneer species on oldfields and
other disturbed sites, a long-lived successional species, and a
physiographic climax species on dry, sandy soils [53,68]. Eastern white
pine is sometimes a component of climax forests on certain sites such as
steep slopes and ridge tops where windfall provides regeneration
Eastern white pine forests frequently establish after disturbance and
are even-aged. However, uneven-aged forests also occur. Eastern white
pine has dominated an uneven-aged old-growth forest in southern Ontario
for at least 700 years. In this forest, canopy gaps created by the
death of individual trees from surface fire or windthrow enable eastern
white pine to regenerate .
Eastern white pine succeeds aspen postdisturbance forests. The diffuse
aspen canopy allows enough light for eastern white pine to regenerate
. Bigtooth aspen colonized and was the early dominant on a burn in
northern Michigan, but 53 years after the fire, eastern white pine and
red maple (Acer rubrum) were dominant .
More shade-tolerant species succeed eastern white pine. In the Boundary
Waters Canoe Area in Minnesota, it begins to be replaced by white spruce
(Picea glauca), eastern white-cedar (Thuja occidentalis), balsam fir
(Abies balsamea), and paper birch (Betula papyrifera) about 360 years
after fire .
Eastern white pine begins producing cones when 5 to 10 years old, but
good seed production does not occur until trees are at least 20 to 30
years old . Good seed years occur every 3 to 5 years, with some
seed produced in intervening years .
Seeds are dispersed primarily by wind. Seeds travel 200 feet (60 m)
within a stand and more than 700 feet (210 m) in the open. Animals also
disperse seeds. Gray squirrel seed caches were responsible for white
pine reproduction under red oak (Quercus rubra) stands in southern New
Hampshire . White-footed mice and red-backed voles bury caches
containing 20 to 30 eastern white pine seeds beneath the litter but on
top of the mineral soil. Caches that escape revisitation and decimation
produce seedlings .
Favorable seedbeds include moist mineral soil, mosses (Polytrichum
spp.), and short grass cover of light to medium density. Dry mineral
soil, pine litter, lichen, and very thin or very thick grass covers are
poor seedbeds in full light but adequate in shade . Eastern white
pine shows very limited delayed emergence the second year after seed
fall, and none after 3 years .
Eastern white pine colonizes disturbed sites, but a nurse crop of aspen
(Populus spp.), birch (Betula spp.), or other pioneer species promotes
best regeneration . When colonizing oldfields, eastern white pine is
more likely to become established in openings than under herbs. Even
though seedling emergence and survivorship are higher under herbs, so
too is seed and seedling predation by rodents .
Eastern white pine seedlings require at least 20 percent of full light
for survival. They achieve maximum height growth in 45 percent of full
light . Early growth is slow, but between 10 and 20 years of age,
the average annual height growth is about 16 inches (40 cm) per year
Eastern white pine does not reproduce vegetatively .
Growth Form (according to Raunkiær Life-form classification)
Reaction to Competition
In Ontario, on upland sites white pine and its associates are rated in decreasing order of shade tolerance as follows: balsam fir (Abies balsamea), sugar maple (Acer saccharum), American beech (Fagus grandifolia), eastern hemlock (Tsuga canadensis), white spruce (Picea glauca), yellow birch, white pine, black spruce (Picea mariana), gray birch (Betula populifolia), red oak Quercus rubra), red maple (Acer rubrum), red pine (Pinus resinosa), jack pine, trembling aspen, bigtooth aspen, and pin cherry (Prunus pensylvanica) (71).
In the seedling stage, white pine is very susceptible to competition because its height growth is slow compared to most of its associates. If white pine survives to the sapling stage, its ability to compete is greatly improved (71).
At either stage, the response to release depends primarily on how strong the competition has been and how long the pine has been in a subordinate position. In general, pines less than 30 years old with at least one-third of their height in live crown respond well, but response declines proportionately with increasing age and decreasing crown length.
White pine may function as a pioneer, as exemplified by its role as the old field pine of New England. It may function as a physiographic climax species on the drier, sandier soils. It may function as a long-lived successional species, and it may be a component of climax forests throughout its range. In Canada, however, it is considered that many of the present white pine stands are edaphic or pyric relicts and that present climatic conditions are against its maintenance as a major species (71).
Pure natural stands of white pine almost never stagnate. Because of differences in vigor, age, and site, differentiation into crown and diameter classes usually occurs. Dominance is more pronounced on the better sites, at the greater stand densities, and in natural stands as compared to plantations (71).
White pine has been regenerated successfully by a wide variety of methods including clearcutting, seed tree, shelterwood, and group selection (44). If there is abundant advanced reproduction, overstory removal is all that is necessary. Clearcutting during or just after heavy seed crops often results in well stocked stands on light soils. Clearcutting in small patches or stands with seed dispersed from adjacent stands is also possible. Because of competition from other vegetation and poor seed crops, mechanical site preparation and planting may be necessary sometimes in conjunction with clearcutting.
Where esthetic considerations are important, group selection may have merit. Probably the most versatile reproduction method is the shelterwood method. By control of overstory density with a series of shelterwood cuts, seedbed conditions may be improved; an accumulation of advanced seedlings is obtained over a period of years; protection of seedlings on hot, dry aspects is afforded; weevil attacks are reduced; and competition from herbaceous and hardwood sprout vegetation is suppressed. Two, three, or more cuts spread over a number of years may be used, but usually white pine can be regenerated successfully with a two-cut shelterwood system. Seed cuts should be timed to take advantage of good seed crops, but timing of the final cut is not critical.
Trees in pure second-growth stands of white pine are noted for their limbiness. The limbs live for about 15 years and persist on the trunk for more than 25 years after they die. In the first log of these stands, there is an average of about 60 limbs (71). Pruning has been recommended to increase quality production. If possible, pruning should begin early when branches are less than 5 cm (2 in) in diameter but not before dominance is expressed. At least 25 percent of the live crown and up to 50 percent in closed stands can be pruned without losses in height growth. To realize full benefits of pruning, only potential crop trees should be pruned and stands should be thinned to maximize growth (24). In Canada, pruning is recommended on fast-growing trees in stands 35 to 80 years old because of the inefficiency of pruning smaller trees and the lengthened rotation and probable growth reduction in older stands (34). This recommendation assumes that the highest returns will accrue if the trees are allowed to grow for another 40 years before harvest.
Much root grafting occurs in white pine stands (12). Regardless of either stand age, soil characteristics, or drainage class, root grafting occurred in 30 to 67 percent of dye-injected trees in five white pine stands in New Hampshire, Maine, and Vermont. Exposure of the root systems indicated that often several trees, rather than two or three, were united by root grafts. Root grafting indicates that competition may be a factor in white pine growth for the first 5 to 10 years of a stand. Thereafter, root grafts begin to form, and the stand may function as a union of grafted trees interspersed with individual trees.
Life History and Behavior
Eastern white pine male strobili open and shed pollen in April through
June, depending on latitude. Fertilization occurs 13 months after
pollination. Cones ripen and seeds are dispersed August through
September, about 2 years after cone initiation [7,26]. Seeds germinate
in the spring . Terminal shoot growth is usually completed by the
end of June .
When June-collected cuttings from 17- and 30-year-old white pine were treated with 0.1 percent indolebutyric acid (IBA) and the fungicide Benlate, 60 and 45 percent, respectively, all of the cuttings produced roots in 16 weeks (36). Cuttings from secondary branches of 13-year-old white pines treated with 5 percent benomyl and 25 percent captan fungicides resulted in root formation on 36 percent of the cuttings. When 0.1 percent or 0.5 percent IBA was added, rooting was 31 percent (64). Multi-applications of N6 benzyladenine at 1,000 p/m to white pine needle fascicles produced roots on 22 percent of all clones tested in 1975 (17).
Scions from the crown of mature trees can be grafted on young stock (31). Side grafts of scions on 3- or 4-year-old white pine stocks seem to be a more reliable method of vegetative propagation than rooted cuttings (71). Buds from main terminal or lateral terminal positions should be used in grafting if early erect growth is desired (1).
Germination is epigeal. Bare mineral soil is not necessary for seed germination; seeds can germinate and survive on both disturbed and undisturbed litter layers (6). Under full exposure to sunlight, moist mineral soil, polytrichum moss, or a shortgrass cover of light to medium density are favorable seedbeds. Dry mineral soil, pine litter, lichen, and very thin or very thick grass covers are unfavorable (71).
Unfavorable seedbed conditions can be corrected by scarification or can be overcome by shade. However, dense, low shade such as that cast by slash piles or hardwood brush is adverse to later survival and the shade of young stands of gray birch (Betula populifolia) or pitch pine reduces growth in the later stages. Overstory shade resulting from a form of shelterwood cut provides good protection during the early stages of growth and is least damaging to later stages (71).
Experience in North Carolina shows that during years of heavy seedfall white pine seedlings develop well in shade cast by logging debris. Some seedlings may die during a hot dry June, however. Thus, the roughest tracts are reserved and regenerated by natural methods during years of high seedfall only (52). On medium to fair sites in the central Appalachians, white pine seedlings can be underplanted in hardwood stands with reasonable success (69). The hardwoods, mostly oaks and hickories, permit enough light to reach the seedlings so some height growth occurs. Normally 3 to 5 years are required for white pine to become established, and if the pines are released 5 to 10 years later, a high proportion outgrow the competing vegetation. Similar results have been reported for 9- to 20-year-old underplanted white pine in Maine, Canada, and South Carolina (16,28,71).
White pine seedlings in the vicinity of recent pine timber cuttings often are attacked by the pales weevil (Hylobius pales). This insect breeds in the fresh stumps and slash; nearby seedlings are girdled and usually killed. Most of the damage occurs during the first 3 years after a cutting and among seedlings less than 5 years old (71).
After the establishment period, light intensity becomes critical to the survival and growth of white pine seedlings. At light intensities less than 10 to 13 percent of full sunlight, survival is uniformly poor; at least 20 percent of full sunlight seems to be required to keep the seedlings alive. As light intensity increases above this point, growth increases proportionately up to full sunlight unless some other condition becomes limiting (71). Diameter growth of planted white pine increased with increased light in clearcut stands in the Piedmont of South Carolina (23). Height growth of underplanted seedlings after 2 years did not differ from that of seedlings planted in a clearcut.
Although young seedlings can survive for several weeks in soils with moisture below the wilting coefficient, growth at a given light intensity is best in the absence of root competition; growth is better when only an overstory offers root competition than when both an understory and an overstory are competing (71). Mineral soil seedbeds plus light intensities greater than 20 percent full sunlight but less than full sunlight support vigorous seedling growth by reducing surface soil temperatures and providing better soil moisture conditions (41). The survival of white pine 2-2 stock was increased on shallow old pasture soils in eastern Ontario when wedge-shaped pieces of peat saturated with water were placed at the bottom of the planting holes to provide water and prevent desiccation during drought periods (61). Two-O stock stored in a refrigerator can be planted until mid-June without significant reduction in survival rate. However, seedlings planted in July and August will not be hardened off by the first fall frost (56).
In some early greenhouse and nursery trials with young seedlings, the optimum supply of nitrogen was shown to be 300 p/m; phosphorus, 350 p/m; potassium, 150 p/m; and calcium, 200 p/m (71).
Early white pine growth is slow. Open-grown trees are about 13 cm (5 in) high when 3 years old; 30 cm (12 in) high when 5 years old; and 137 cm (54 in) high when 8 to 10 years old. Thereafter, height growth may be quite rapid. Between 10 and 20 years old, open-grown dominant trees have grown as much as 137 cm (54 in) in height in a single year. Annual increments of 91 cm (36 in) are not uncommon, but average height growth of dominant trees during this period is about 41 cm (16 in) (71). Usually terminal growth occurs within a 30-day period (6) and normally is completed by July 1 (56).
Seed Production and Dissemination
Cones are green when immature and turn yellow-green to light brown when ripe. Cones that float in linseed oil are considered ripe. Cones should be collected from trees having superior growth and form. Widely spaced dominant trees with full crowns produce the most seeds per cone (39).
In a comprehensive German study of white pine seed production, it was found that a 90-year-old stand produced about 73 kg of seeds per hectare (65 lb/acre); a comparable 60-year-old stand produced only one-fifth as much. In these stands, dominant trees produced twice as many cones as codominant trees (71). In Maine, intermediate density stands 27.6 m²/ha (120 ft²/acre) produced 4,430,000 viable seeds per hectare (1,793,220/acre) in a good seed year (29). In high density stands 42.9 m²/ha (187 ft²/acre), seedfall was 36 percent less and in low density stands 18.4 m²/ha (80 ft²/acre), seedfall was 30 percent less than in the intermediate density stands.
There are 58,400 seeds per kilogram (26,500/1b) with a range from 38,600 to 116,800/kg (17,500 to 53,000/1b) (39). In a study of 250 different parents from all parts of the white pine range, the number of good seeds per cone ranged from 0 to 73. The lowest sets were found in stands at the extremes of the range.
Most of the seeds are dispersed within the month following cone maturity. The seeds travel at least 60 m (200 ft) within a white pine stand and more than 210 m (700 ft) in the open (71). Gray squirrels were found responsible for much of the white pine reproduction under mature red oak stands in southern New Hampshire; they bury and recover the seeds (3).
Flowering and Fruiting
Trees may start to bear female flowers when 5 to 10 years old (71). In the Philadelphia area, quantity production of female flowers does not begin until the trees are about 6 m (20 ft) tall. At that size, 200 to 300 flowers may be produced in 1 year; the number is only a little greater on larger or older trees. Few or no male flowers appear during the early flowering years. Femaleness persists even on older trees 30 to 61 cm (12 to 24 in) in diameter, although trees of this size do produce small to moderate amounts of pollen (71).
The pattern of flowering in white pine is uncertain. In the Philadelphia area, the better flowering trees tend to produce about the same number of female flowers every year, with some exceptions; male flowers, however, do not appear every year (71). Fertilization occurs about 13 months after pollination, and cones mature usually during August and September of the second year (39). Trees have borne cones at 5 to 10 years of age, but good seed production cannot be expected until the trees are 20 to 30 years old (30).
Reproduction and Life History
Pinus strobus plants become reproductively mature between 5 and 10 years of age, but do not reach peak strobilus production until the age of about 20 years. Pollen is dispersed by air between April and June (depending on latitude) and reaches the first-year megastrobili soon thereafter. Upon pollination, 13 months are required for fertilization of the ovule within the slightly enlarged one-year cone. The winged seeds mature during the second year and are dispersed by gravity and air at the end of the second year. The seed cones (megastrobili) drop from the tree soon after the seeds are dispersed.
Seeds of P. strobus are eaten by a variety of wildlife, especially small mammals. Deer and other larger mammals will browse the species when other winter forage has been exhausted. Source documents: Price (1989), Burrows and Tyrl (2001).
Growth and Yield
Periodic height growth increment of dominant and codominant trees in southern Appalachian natural white pine stands occurs at younger ages on the better sites and tends to decline more rapidly. Height growth of both planted and natural white pine is slow during the first 2 to 3 years. Afterwards, growth accelerates rapidly, peaking at an average annual rate of 1 m (3 ft) between 10 and 15 years on site index 80 (base 50 years) (6). By age 55, the rate of annual growth is about equal on all sites (9). For example, in stands with a site index of 36.6 m (120 ft), maximum growth of 1.0 m (3.4 ft) per year occurred at age 14; whereas, with a site index of 18.3 m (60 ft), maximum growth of 0.5 m (1.5 ft) per year did not occur until age 23. By age 55, however, annual growth for all sites was about 0.3 m (1.0 ft) per year (fig. 1).
Figure 1-Curves of annual increment (A) and cumulative
height (B) for selected site indices. These curves show the
changing pattern of growth with level of site index (9).
Diameter growth may be as rapid as 2.5 cm (1 in) per year or as slow as 2.5 cm (1 in) in 40 years. Dominant trees ordinarily grow at the rate of 1 to 2 rings per 5 mm (5 to 10/in) to an age of 250 years. In fully stocked stands on average sites, the average tree diameter increases at a nearly uniform rate of 2.5 cm (1 in) every 5 to 6 years (71).
Generally, rates of growth in basal area, cubic volume, and sawtimber volume in natural southern Appalachian stands tend to be slower than those in old-field plantations. For example, maximum mean annual increment in cubic volume occurs at 60 to 70 years in natural stands and at about 25 years in plantations. Similarly, sawtimber volume in natural stands is still increasing at 100 years, though very slowly. In New England stands, mean annual increment in cubic volume occurs at age 40 to 50 (8). Sustained cubic volume growth extends from about age 30 to 90. Mean annual growth peaks at 8.6 m/ha (615.0 fbm/acre). In New England, a stocking guide for white pine has been prepared (55) (fig. 2).
Figure 2-Stocking guide for nearly pure even-aged white pine
stands, showing basal area per acre, number of trees per acre,
and mean d.b.h. for trees in the main crown canopy (55).
The A curve represents 80 percent stocking, and stands above it are considered overstocked. The B curve represents minimum stocking for full site utilization and stands that fall below are considered understocked. Stands between the A and B curves are considered adequately stocked. Where a particular stand might fall in the guide is based on basal area per acre, number of trees per acre, and mean d.b.h. for trees in the main canopy. Tables have been prepared for different stand ages, site and stocking percent, and cubic and sawtimber yield (table 1) (43). Yields of about 504 m³/ha (36,000 fbm/acre) at 50 years in nearly fully stocked managed stands are entirely possible. The average white pine stand in New England grows from 4.2 to 11.2 m³/ha (300 to 800 fbm/acre) per year depending on age, site index, and stocking (41). Site index for eastern white pine is determined from the average height of dominant trees at age 50 years.
Table 1- Yields from fully stocked, natural stands of eastern white pine in New England (41) Site index at base age 50 years Stand age (yr) 15 m or 50 ft 12 m or 70 ft 27 m or 90 ft m³/ha Sawtimber¹ 40 108 209 405 60 236 456 - 80 349 674 - 100 440 852 - Pulpwood² 20 100 137 187 40 247 339 464 60 334 458 628 80 388 533 731 100 425 583 800 fbm/acre Sawtimber 40 7,729 14,948 28,909 60 16,858 32,604 - 80 24,898 48,152 - 100 31,460 60,845 - Pulpwood 20 1,423 1,952 2,677 40 3,526 4,836 6,632 60 4,771 6,543 8,974 80 5,550 7,611 10,439 100 6,077 8,334 11,431 ¹Volume to a 15 cm (6.0 in) diameter top outside bark- fbm measured using the International 0.25-inch log rule.
²Volume to an 8 cm (3.0 in) diameter top inside bark. For more detailed information, refer to publications on the growth and yield of white pine in natural stands and plantations prepared specifically for the various parts of the range (6,10,41,49,55,57).
Evolution and Systematics
Systematics and Taxonomy
A disjunct population of white pines in southern Mexico and Guatemala was first described as P. strobus var. chiapensis and is still treated as such by a few authors (e.g. Farjon 1997, Flora Neotropica Monograph 75: 215). It was raised to specific rank as P. chiapensis by Andresen (1964, Phytologia 10: 417), a treatment now accepted by a majority of authors and supported by genetic research, which shows it is very distinct genetically, sharing no alleles with P. strobus and forming a distinct clade of its own, sister to two clades of American and Asian species (Liston et al. 2003, Proc. Fourth International Conifer Conference: 107-114; Syring et al. 2007a, Systematic Biology 56: 163-181; Syring et al. 2007b, Syst. Bot. 32: 703-717).
Although fairly similar to P. strobus in foliage morphology, P. chiapensis differs clearly in cone morphology, here showing a much closer resemblance to several Eurasian white pines, notably P. peuce from SE Europe and P. dalatensis from Vietnam.
Physiology and Cell Biology
Physiology and Biochemistry
Molecular Biology and Genetics
Races and Hybrids Eastern white pine is represented in the United States by the typical variety, Pinus strobus var. strobus. Chiapas white pine, P. strobus var. chiapensis, is native in the mountains of southern Mexico and Guatemala. Four horticultural varieties have been recognized in Connecticut (68).
Eastern white pine crosses readily with western white pine (Pinus monticola), Balkan pine (P. peuce), blue pine (P. griffithii), and Japanese white pine (P. parviflora). It can also be crossed with limber pine (P. flexilis) and Mexican white pine (P. ayacahuite) (21). The cross P. strobus x griffithii is more vigorous than P. strobus in Northern Ohio and more winter hardy than P. griffithii (37).
Statistics of barcoding coverage: Pinus strobus L.
Public Records: 0
Specimens with Barcodes: 1
Species With Barcodes: 1
Barcode data: Pinus strobus
Statistics of barcoding coverage: Pinus strobus
Public Records: 19
Specimens with Barcodes: 29
Species With Barcodes: 1
Molecular Biology and Genetics
IUCN Red List Assessment
Red List Category
Red List Criteria
National NatureServe Conservation Status
Rounded National Status Rank: N5 - Secure
Rounded National Status Rank: N5 - Secure
NatureServe Conservation Status
Rounded Global Status Rank: G5 - 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).
Pinus strobus is commonly cultivated as a shade and ornamental tree. Krüssmann (1985) listed 18 principal forms and cultivars and Dirr (1998) noted that the cultivars are too numerous to be listed in detail in his general volume on woody plants.
Pests and potential problems
The white pine weevil is the tree's greatest insect pest affecting both timber quality and volume. Terminal leaders may be killed repeatedly and result in such serious stem crooks that the tree has reduced merchantable saw timber value.
The pales weevil is an insect that often attacks white pine seedlings in areas where white pine timber has been cut recently. Cone crops may be destroyed by the pine cone beetle. This insect compounds the problem of infrequent seed years and is a serious threat to white pine management.
Diseases, including white pine blister rust, red ring rot, root rot, wood decay, and certain needle fungi, cause losses in white pine stands. Such natural elements as snow, ice, and wind may also cause damage to white pine.
The frequency of eastern white pine is lower in today's forests than in
presettlement forests. Eastern white pine was heavily logged in the
1800's in the north-central United States. Regeneration after the early
logging was poor because of the lack of seed trees and the destruction
of remaining seedlings and saplings by fire [39,41]. In the
northeastern United States, eastern white pine temporarily increased in
abundance through colonization of abandoned fields and pastures. Many
of these stands reached commercial maturity by the early 1900's and were
harvested. Hardwoods, which had invaded the understory, now dominate
many of these old-field sites .
The two-cut shelterwood method is recommended for maximizing
regeneration of eastern white pine. The first cut removes 40 to 60
percent of the overstory, and the final cut occurs 5 to 10 years later
after seedlings are well established. Established individuals respond
well to release .
Two of the more damaging pests of eastern white pine are the white pine
weevil (Pissodes strobi) and white pine blister rust (Cronartium
ribicola) [67,68]. Eastern white pine is infrequently planted in the
north-central region because of the inevitable damage caused by the rust
. See Fire Management slot for control of the white pine cone
beetle (Conophthorus coniperda), which is often responsible for complete
The growth rate of all pine species in the New Jersey Pine Barrens
except eastern white pine has decreased since the 1950's; this decrease
in growth rate may be the caused by acid rain . Eastern white pine
germination and emergence are not greatly affected by soil acidity
caused by acid rain [47,50].
Cultivars, improved and selected materials (and area of origin)
There are no documented varieties for reforestation purposes. Local or regional ecotypes are typically utilized for this purpose. There are several varieties available for ornamental applications. Seeds and seedlings are available from most eastern conifer nurseries.
White pine seedlings require weed control for the first few years after outplanting. Chemical and/or mechanical control can be used, preferably starting the year before planting.
Management of white pine should focus on thwarting the white pine weevil where straight trunks and tree form is desired. Growing white pine where there will be partial shade on the developing saplings and pole-sized trees (especially on the terminal leader) seems to reduce infestation by the weevil. Thus growing white pine in mixed uneven aged stands is a good idea to avoid this pest and those described below.
Relevance to Humans and Ecosystems
Value for rehabilitation of disturbed sites
Eastern white pine is used extensively for stabilizing strip-mine
spoils, especially in northern Appalachian coal fields. Eastern white
pine has a lower soil pH limit of 4.0. Seedlings tolerate limited shade
from herbaceous ground cover better than other pine species [58,64].
Eastern white pine growth is adversely affected by high levels of
soluble salts and by the depth of the mine soil. These effects can be
avoided by selecting nonpyritic sandstone material for surface placement
and by minimizing soil compaction .
Eastern white pine planted on bituminous coal mine spoils in
Pennsylvania averaged 6.1 inches (15.5 cm) d.b.h. and 27 feet (8.2 m) in
height after 30 years .
Importance to Livestock and Wildlife
species. Songbirds and small mammals eat eastern white pine seeds.
Snowshoe hares, white-tailed deer, and cottontails browse the foliage;
the bark is eaten by various mammals . Pocket gophers graze the
roots of seedlings and young trees .
Northeastern pine forests can support a rich community of breeding birds
. Bald eagles build nests in living eastern white pine, usually at a
main branch located below the crown top . Eastern white pine,
especially those with broken tops, provide valuable habitat for
cavity-nesting wildlife .
Young black bear cubs use large eastern white pine to climb to safety.
In northeastern Minnesota, black bear mothers and cubs spent more than
95 percent of the time in April and May within 600 feet (180 m) of
either an eastern white pine or an eastern hemlock larger than 20 inches
(50 cm) in d.b.h. .
Wood Products Value
States and Canada. The soft wood is of medium strength, easily worked,
and stains and finishes well. It is used for doors, moldings, trim,
siding, panelling, cabinet work, and furniture [20,68].
deer . Although available, it was not browsed by moose in Ontario .
White pines are useful in urban plantings. Trees grown from seeds obtained in Prince Edward Island, Nova Scotia, or in adjacent regions of New Brunswick, Maine, and New Hampshire may be more suitable than trees obtained from other regions (27). They usually have more compact crowns and are more resistant to snowbreak; they grow more slowly, have darker blue-green color, and seem to be more resistant to air pollutants than trees from other origins.
White pine has been used extensively for stabilizing strip-mine spoils. In the anthracite region of Pennsylvania, white pine survived well on spoils that fell within the pH range 5.1 to 6.5, and growth was better on lower slopes of the spoils than on upper slopes (18). On bituminous spoils in West Virginia, white pine survived best on spoils having a pH greater than 4.0 (13). Growth on the spoils was slow for the first 5 years, but total height exceeded that of Scotch pine (P. sylvestris), and red pine at 10 years.
The bark of white pine is used as an astringent and an expectorant, and the wood has been used to produce white pine tar, which is used as an antiseptic, expectorant, and protective (38). White pine wood has medium strength, is easily worked, and stains and finishes well. It is used for furniture, patterns, matches, and many other items. White pine is also planted for Christmas trees. The foliage has a good color and responds well to shearing (19).
Timber: The wood of white pine is light, durable, and easy to work. It is good lumber for toys, boxes, cabinet work, and similar items.
Christmas tree and ornamental: White pine is used occasionally in Christmas tree plantations and as ornamental planting in landscaping around homes and office buildings. It can also be sheared as a hedge.
Wildlife: It has fair wildlife value. Gray and red squirrels, deer, mice and 16 species of songbirds have been known to eat the seed.
Erosion control: White pine is frequently used for windbreaks and screens along fields new right-of-ways and around campsites.
Where is it Grown
Daniel Moerman’s online database of Native American ethnobotanical uses includes 90 records for Pinus strobus (see also Moerman, 1998). The uses are too numerous to list fully here. Mainly, the bark was used in poultices for various ailments ranging from colds to coughs, pain, and skin disorders. An infusion of the bark also was ingested for coughs and as an emetic. An infusion of the young growth was used to treat a variety of ailments ranging from lung to kidney disorders and boiled young growth was used as an inhalant for coughs and colds. The pitch was applied to boils.
Eastern white pine is an important commercial timber species that produces superior-quality cut lumber for construction uses. The soft wood is easily worked, and the species also provides lumber for cabinetry, furniture-making, handcrafts, and other minor uses.
Pines in general are toxic. Cattle and to some extent sheep that ingest needles, young shoots, or bark during pregnancy are prone to producing weak or dead calves, apparently because some compounds in pines disrupt reproductive hormones (Burrows and Tyrl, 2001). However, apparently Pinus strobus in particular has not been studied. Most of the problems associated with this toxicity are in western states where other species of pines occur. In areas where other winter browse has been exhausted, deer that ingest pines apparently do not suffer any symptoms of poisoning.
|This article includes a list of references, but its sources remain unclear because it has insufficient inline citations. (December 2012)|
Pinus strobus, commonly known as the eastern white pine, white pine, northern white pine, Weymouth pine, and soft pine is a large pine native to eastern North America. It occurs from Newfoundland west through the Great Lakes region to southeastern Manitoba and Minnesota, and south along the Appalachian Mountains and upper Piedmont to northernmost Georgia and perhaps very rarely in some of the higher elevations in northeastern Alabama, and is planted in areas near its natural range where summer temperatures are fairly moderate.
This tree is known to the Native American Haudenosaunee (Iroquois nation) as the Tree of Peace. It is known as the Weymouth pine in the United Kingdom, after George Weymouth who brought it to England in 1620.
Pinus strobus is found in the Nearctic Temperate broadleaf and mixed forests Biome of eastern North America. It prefers well-drained soil and cool, humid climates, but can also grow in boggy areas and rocky highlands. In mixed forests, this dominant tree towers over all others, including the large broadleaf hardwoods. It provides food and shelter for numerous forest birds, such as the Red Crossbill, and small mammals such as squirrels.
Eastern white pine forests originally covered much of northeastern North America. Only one percent of the old-growth forests remain after the extensive logging operations that existed from the 18th century into the early 20th century.
Old-growth forests, or virgin stands, are protected in Great Smoky Mountains National Park. Other protected areas with known virgin forests, as confirmed by the Eastern Native Tree Society, include: Algonquin Provincial Park, Quetico Provincial Park, and Algoma Highlands, Ontario; Huron Mountains, Estivant Pines, Porcupine Mountains State Park, and the Sylvania Wilderness Area in the Upper Peninsula of Michigan; Hartwick Pines State Park in the Lower Peninsula of Michigan; Menominee Indian Reservation, northeastern Wisconsin; the Lost 40 Scientific and Natural Area (SNA) near Blackduck, and Boundary Waters Canoe Area Wilderness, Minnesota; White Pines State Park, Illinois; Cook Forest State Park, Hearts Content Scenic Area, and Anders Run Natural Area, Pennsylvania; and the Linville Gorge Wilderness, North Carolina.
Small groves or individual specimens of old-growth eastern white pines are found across the range of the species, including: Ordway Pines, Maine; Ice Glen, Massachusetts; and numerous sites in Adirondack Park, New York. Many sites with conspicuously large pines represent advanced old field succession. The tall white pine stands in the Mohawk Trail State Forest and at the William Cullen Bryant Homestead in Massachusetts are old field examples.
As an introduced species, Pinus strobus is now naturalizing in the Outer Eastern Carpathians subdivision of the Carpathian Mountains, in the Czech Republic and southern Poland. It has spread from specimens planted as ornamental trees in gardens and parks.
Like all members of the white pine group, Pinus subgenus Strobus, the leaves ('needles') are in fascicles (bundles) of five (rarely 3 or 4), with a deciduous sheath. They are flexible, bluish-green, finely serrated, and 5–13 cm (2.0–5.1 in) long, and persist for 18 months, i.e. from the spring of one season to the autumn of the next, when they are shed by abscission.
The cones are slender, 8–16 cm (3.1–6.3 in) long (rarely longer than that) and 4–5 cm (1.6–2.0 in) broad when open, and have scales with a rounded apex and slightly reflexed tip. The seeds are 4–5 mm (0.16–0.20 in) long, with a slender 15–20 mm (0.59–0.79 in) wing, and are wind-dispersed. Cone production peaks every 3 to 5 years.
Mature trees can easily be 200 to 250 years old. Some white pines live over 400 years. A tree growing near Syracuse, New York was dated to 458 years in the late 1980s and trees in both Wisconsin and Michigan have approached 500 years in age.
The eastern white pine, Pinus strobus, has the distinction of being the tallest tree in eastern North America. In natural pre-colonial stands it is reported to have grown to as tall as 70 m (230 ft). There is no means of accurately documenting the height of trees from these times, but eastern white pine may have reached this height on rare occasions. Even greater heights have been attributed to the species referenced in popular accounts such as Robert Pike's "Tall Trees, Tough Men", but such accounts are unverifiable.
Total trunk volumes of the largest white pines are around 28 m3 (990 cu ft) with some past giants reaching a possible 37 or 40 m3 (1,300 or 1,400 cu ft). Photographic analysis of giant pines suggests volumes closer to 34 m3 (1,200 cu ft).
Pinus strobus grows approximately 1 m (3.3 ft) per year between the ages of 15 and 45 years, with slower height increments before and after that age range. The current tallest eastern white pines reach between 50–57.55 m (164.0–188.8 ft), as determined by the NTS—Native Tree Society. Three locations in the Southeastern United States and one site in the Northeastern United States have been identified with trees reaching 55 m (180 ft) tall.
The southern Appalachians have the most locations and the tallest trees in the present day range of Pinus strobus. One survivor is a specimen known as the "Boogerman Pine" in the Cataloochee Valley, of Great Smoky Mountains National Park. At 57.55 m (188.8 ft) tall, it is the tallest accurately measured tree in North America east of the Rocky Mountains. It has been climbed and measured by tape drop by the NTS. Before it lost its top in Hurricane Opal in October 1995, the Boogerman Pine was 63 m (207 ft) tall, as determined by Will Blozan and Robert Leverett using ground-based measurement methods.
The tallest eastern white pines in Hartwick Pines State Park of northern Michigan reach 45–48 m (148–157 ft) in height.
In the Northeasern U.S., 8 sites in four states currently have trees over 48 m (157 ft) in height, as confirmed by NTS. The Cook Forest State Park of Pennsylvania has the largest collection of 45 m (148 ft) eastern white pines in the Northeast, with 110 trees measuring that height or more. The park's "Longfellow Pine" is the tallest eastern white pine in the Northeast currently. It has a height of 55.96 m (183.6 ft), determined by being climbed and measured by tape drop.
The Mohawk Trail State Forest of Massachusetts has 83 trees reaching 45 m (148 ft) in height or more, of which six exceed 48.8 m (160 ft). This is the largest collection of 45 m (148 ft) tall eastern white pines in New England. The "Jake Swamp Tree" located here is 51.54 m (169.1 ft) tall. It is the tallest accurately measured tree of any species within New England. Precise measurements are maintained on this tree by NTS.
A private property in Claremont, New Hampshire has about sixty white pines in the 45 m (148 ft) height range. Beyond the above locations, sites with 45 m (148 ft) specimens typically have from one to fifteen trees, with most sites having less than ten trees.
Diameters of the larger pines range from 1.0-1.6 m (3–5 ft), which translates to a circumference (girth) range of 3.1–5.0 m (10.2–16.4 ft). However, singled-trunk white pines in both the Northeast and Southeast with diameters over 1.45 m (4 ft 9 in) are exceedingly rare. Notable big pine sites of 40 ha (99 acres) or less will often have no more than 2 or 3 trees in the 1.2 to 1.4 m (3 ft 11 in to 4 ft 7 in) diameter class.
Unconfirmed reports from colonial America gave diameters of virgin white pines of up to 2.4 m (8 ft).
Mortality and disease
Because the eastern white pine tree is somewhat resistant to fire, mature survivors are able to re-seed burned areas. In pure stands mature trees usually have no branches on the lower half of the trunk. The white pine weevil (Pissodes strobi) and White Pine Blister Rust (Cronartium ribicola), an introduced fungus, can damage or kill these trees.
Mortality from White Pine Blister Rust in mature pine groves was often 50–80% during the early 20th century. The fungus must spend part of its life cycle on alternate hosts of the Ribes genus, the native gooseberry or wild currant. Foresters proposed that if all the alternate host plants were removed that White Pine Blister Rust might be eliminated. A very determined campaign was mounted and all land owners in commercial pine growing regions were encouraged to uproot and kill all native gooseberry and wild currant plants. The ramifications for wildlife and habitat ecology were of less concern at the time than timber industry protection.
Today native wild currants are relatively rare plants in New England, and planting wild currants or wild gooseberries is strongly discouraged, or even illegal in some jurisdictions. As an alternative, new strains of commercial currants have been developed which are highly resistant to White Pine Blister Rust. Possibly due to hard work of the foresters, mortality in White Pines from rust is only about 3% today.
During the age of sailing ships, tall white pines with high quality wood were known as mast pines. Marked by agents of the Crown in colonial times with the broad arrow, they were reserved for the British Royal Navy.
The British built special barge-like vessels which could carry up to 50 pine trunks destined to be ship masts. The wood was often squared immediately after felling to fit in the holds of ships better. A 30 m (100 ft) mast was about 91 cm × 91 cm (3 ft × 3 ft) at the butt and 61 cm × 61 cm (2 ft × 2 ft) at the top, while a 37 m (120 ft) mast was a giant 1.2 m × 1.2 m (4 ft × 4 ft) at the bottom and 76 cm (30 in) at the top. The original masts on the USS Constitution (Old Ironsides) were single trees but later they were laminated to better withstand cannonballs.
Marking of large specimens by the Crown was very controversial in the colonies, and their de facto seizure was a point of great contention among the colonists and played a significant role in the events leading to the American Revolution. During the American Revolution it became a great sport for the patriots to see how many of the King’s trees one could cut down and haul off.
An unusual large, lone, white pine was found in colonial times, in coastal South Carolina along the Black River (far south of its normal range), and the king's mark was put upon this particular tree, giving rise to the town of Kingstree.
Eastern white pine is now widely grown in plantation forestry within its native area. The species was imported in 1620 to England by Captain George Weymouth, who planted it for a timber crop, but had little success because of White Pine Blister Rust disease.
Old growth pine in the Americas, of various Pinus species, was a highly desired wood since huge, knot-free boards were the rule rather than the exception. Pine was common and easy to cut, thus many colonial homes used pine for paneling, floors and furniture. Pine was also a favorite tree of loggers since pine logs can still be processed in a lumber mill a year or more after being cut down. In contrast, most hardwood trees such as cherry, maple, oak, and ash must be cut into 1” thick boards immediately after felling or large cracks will develop in the trunk which can render the wood worthless.
Freshly cut eastern white pine is creamy white or a pale straw color but pine wood which has aged many years tends to darken to a deep rich tan. Occasionally one can find light brown pine boards with unusual yellowish-golden or reddish-brown hues. This is the famous "pumpkin pine". It is generally thought that slow growing pines in old-growth forests accumulate colored products in the heartwood, but genetic factors and soil conditions may also play a role in rich color development.
Although eastern white pine was frequently used for flooring in buildings constructed before the U.S. Civil War, the wood is soft and consequently you will find cup-shaped depressions from normal wear and tear on almost every old white pine floor. George Washington realized this would happen and wisely made his Mount Vernon floors out of yellow pine which is much harder.
This wood is also favoured by pattermakers for its easy working.
Foods and medicines
Eastern white pine needles contain five times the amount of Vitamin C (by weight) of lemons and make an excellent herbal tea. The cambium is edible. It is also a source of resveratrol. Linnaeus noted in the 18th century that cattle and pigs fed pine bark bread grew well, but he personally did not like the taste. Caterpillars of Lusk's Pinemoth (Coloradia luski) have been found to feed only on Pinus strobus.
Pine tar is produced by slowly burning pine roots, branches, or small trunks in a partially smothered flame. Pine tar mixed with beer can be used to remove tapeworms (flat worms) or nematodes (round worms). Pine tar mixed with sulfur is useful to treat dandruff, and marketed in present day products. Pine tar can also be processed to make turpentine.
- Native American traditional uses
The name “Adirondack” is an Iroquois word which means tree-eater and referred to their neighbors (more commonly known as the Algonquians) who collected the inner bark of this tree, Picea rubens, and others during times of winter starvation. The white soft inner bark (cambial layer) was carefully separated from the hard, dark brown bark and dried. When pounded this product can be used as flour or added to stretch other starchy products.
The young staminate cones were stewed by the Ojibwe Indians with meat and were said to be sweet and not pitchy. In addition, the seeds are sweet and nutritious, but not as tasty as those of some of the western nut pines.
Pine resin (sap) has been used by various tribes to waterproof baskets, pails, and boats. The Chippewa also used pine resin to successfully treat infections and even gangrenous wounds. This is because pine resin apparently has a number of quite efficient antimicrobials. Generally a wet pulp from the inner bark was applied to wounds, or pine tar mixed with beeswax or butter and used as a salve was, to prevent infection.
Pinus strobus is cultivated by plant nurseries as an ornamental tree, for planting in gardens and parks. The species is low-maintenance and rapid growing as a specimen tree. With regular shearing it can also be trained as a hedge. Some cultivars are used in bonsai. 
- Pinus strobus Nana Group — ave. 91 cm (3 ft) tall by 1.2 m (4 ft) wide. MBG: Pinus strobus (Nana Group)
Smaller specimens are popular as live Christmas Trees. Eastern white pines are noted for holding their needles well, even long after being harvested. They also are well suited for people with allergies, as they give little to no aroma. A standard 1.8-meter (6 ft) tree takes approximately 6 to 8 years to grow in ideal conditions. Sheared varieties are usually desired because of their stereotypical Christmas Tree conical shape, as naturally grown ones can become too thick for larger ornaments, or grow bushy in texture. The branches of the Eastern White Pine are also widely used in making holiday wreaths and garland because of their soft, feathery needles.
Sprigs of Eastern White Pine were worn as badges as a symbol of Vermont identity during the Vermont Republic and appears in a stained glass window at the Vermont State House, on the Flag of Vermont and the naval ensign of the Commonwealth of Massachusetts.
- Carey, Jennifer H. 1993. Pinus strobus. In: Fire Effects Information System, [Online]. U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station, Fire Sciences Laboratory (Producer). 2013, August 12 accessed 12 August 2013
- USDA: Native distribution map for Pinus strobus, accessed 1.13.2013
- Moore, Gerry; Kershner, Bruce; Craig Tufts; Daniel Mathews; Gil Nelson; Spellenberg, Richard; Thieret, John W.; Terry Purinton; Block, Andrew (2008). National Wildlife Federation Field Guide to Trees of North America. New York: Sterling. p. 77. ISBN 1-4027-3875-7.
- Beck, D.E. (1971). "Height-Growth Patterns and Site Index of White Pine in the Southern Appalachians". Forest Science 17 (2): 252–260.
- NTS—Native Tree Society
- Luthringer, D.J. 2009. Big Trees of Cook Forest. Pennsylvania Forests 100(3):8-12.
- Jake Swamp Tree: 51.54m in August 2008.
- The Jake Swamp Tree was climbed and measured by tape drop in November 1998 and October 2001. It was scheduled to be climbed and measured a third time in November 2008.
- Ling, H. 2003. The Eastern White Pine. Native Plant Society of NJ Newsletter Winter 2003 pp 2–3.
- Lombard K. and J. Bofinger. 1999. White Pine Blister Rust. NH Div. of Forests and Lands.
- Nizalowski, E. 1997. The mystery of the Pumpkin Pine. Newark Valley Historical Society, Newark, NY.
- Sloane, E. 1965. A Reverence for Wood. Balantine Books, NY.
- Erichsen-Brown, C. 1979. Medicinal and Other Uses of North American Plants. Dover Publications, NY.
- Native American Ethnobotany (University of Michigan - Dearborn), accessed 1.13.2013
- Fernald, M., A. Kinsey, and R. Rollins. 1943. Edible Wild Plants. Harper & Row, NY.
- from Lady Bird Johnson Wildflower Center Native Plant Information Network (NPIN); species account, horticultural information, + photographs . accessed 1.13.2013
- MBG—Missouri Botanical Garden Kemper Center for Home Gardening: Pinus strobus (eastern white pine) . accessed 1.13.2013
- Christmas tree.org
- Ontario symbols . accessed 1.13.2013
- Netstate.com: Maine State Flower
- Conifer Specialist Group (1998). Pinus strobus. 2006. IUCN Red List of Threatened Species. IUCN 2006. www.iucnredlist.org. Retrieved on 12 May 2006.
- Pinetum.org: Cone photo from Arboretum de Villardebelle
- Eastern Native Tree Society - Boogerman Pine photo gallery
- The Monday Garden: The Eastern White Pine
Names and Taxonomy
strobus L. . Little  recognizes two varieties: the typical
variety and Chiapas white pine (Pinus strobus var. chiapensis Mart.).
Chiapas white pine, native to the mountains of southern Mexico and
Guatemala, is also recognized as a separate species, Pinus chiapensis
(Mart.) Andresen . This writeup discusses the typical variety,
eastern white pine.
northern white pine