Pinus ponderosa, commonly known as the ponderosa pine,[Safford, H.D. 2013. Natural Range of Variation (NRV) for yellow pine and mixed conifer forests in the bioregional assessment area, including the Sierra Nevada, southern Cascades, and Modoc and Inyo National Forests. Unpublished report. USDA Forest Service, Pacific Southwest Region, Vallejo, CA, [1]]
Pinus ponderosa grows in various erect forms from British Columbia southward and eastward through 16 western U.S. states and has been introduced in temperate regions of Europe and in New Zealand. It was first documented in modern science in 1826 in eastern Washington near present-day Spokane (of which it is the official city tree).
Description
Pinus ponderosa is a large
pine (
evergreen) tree. The bark helps distinguish it from other species. Mature to overmature individuals have yellow to orange-red bark in broad to very broad plates with black crevices.
Younger trees have blackish-brown bark,
referred to as "blackjacks" by early loggers. Ponderosa pine's five varieties, as classified by some botanists, can be identified by their characteristically bright-green needles (contrasting with blue-green needles that distinguish
Jeffrey pine). The Pacific variety has the longest——and most flexible needles in plume-like fascicles of three. The Columbia ponderosa pine has long——and relatively flexible needles in fascicles of three. The Rocky Mountains variety has shorter——and stout needles growing in scopulate (bushy, tuft-like) fascicles of two or three. The southwestern variety has , stout needles in fascicles of three (averaging ). The central High Plains variety is characterized by the fewest needles (1.4 per whorl, on average); stout, upright branches at narrow angles from the trunk; and long green needles——extending farthest along the branch, resembling a fox tail. Needles are widest, stoutest, and fewest (averaging ) for the species.
The egg-shaped cones, which are often found in great number under trees, are long. They are purple when first chewed off by squirrels, but become more brown and spherical as they dry.
Sources differ on the scent of P. ponderosa. Some state that the bark smells of turpentine, which could reflect the dominance of terpenes (alpha- and beta-pinenes, as well as delta-3-carene).
Size
Pass, Oregon]]The National Register of Big Trees lists a ponderosa pine that is tall and in circumference.
In January 2011, a Pacific ponderosa pine in the Rogue River–Siskiyou National Forest in Oregon was measured with a laser to be high. The measurement was performed by Michael Taylor and Mario Vaden, a professional
arborist from
Oregon. The tree was climbed on October 13, 2011, by Ascending The Giants (a tree-climbing company in Portland, Oregon) and directly measured with tape-line at high.
As of 2015, a
Pinus lambertiana specimen was measured at ,
which surpassed the ponderosa pine previously considered the world's tallest pine tree.
Taxonomy
Pinus ponderosa was scientifically described and named by Charles Lawson working from information provided by David Douglas in 1836.
The taxonomy of the ponderosa pine is heavily disputed by botanists and foresters. As recently as 2013 Robert Z. Callaham writing a research paper for the US Forest Service claimed that it is a single species from the Rocky Mountains to the Pacific coast divided into five subspecies.
Subspecies and varieties
-
Pinus ponderosa var. arizonica (Engelm.) Shaw
- : This variety is listed in the Flora of North America,
-
Pinus ponderosa var. benthamiana (Hartw.) Vasey
- : The Olympic Peninsula in Washington State, Oregon west of the Cascade Range, the whole of California, and far north eastern Nevada. This variety is recognized by PLANTS as the correct name for subspecies critchfieldiana.
- : Four corners transition zone, including southern Colorado, southern Utah, northern and central New Mexico and Arizona, westernmost Texas, and a single disjunct population in the far northwestern Oklahoma panhandle.
-
Pinus ponderosa var. pacifica J.R. Haller & Vivrette – Pacific ponderosa pine
- : on coastal-draining slopes of major mountain ranges in California, and in southwestern Oregon, Washington.
-
Pinus ponderosa var. ponderosa Douglas ex C. Lawson – Columbia ponderosa pine, North plateau ponderosa pine
- : This is the autonymic variety of the species.
-
Pinus ponderosa var. scopulorum (George Engelmann in S.Watson) E. Murray, Kalmia 12:23, 1982 – Rocky Mountain ponderosa pine
- : Variety scopulorum is recognized by WFO,
-
Pinus ponderosa var. washoensis (H. Mason & Stockw.) J.R. Haller & Vivrette – Washoe pine
- : Predominantly in northeastern California, and into Nevada and Oregon, at , upper mixed-conifer to lower subalpine habitats.
Distributions of the subspecies in the United States are shown in shadow on the map. Distribution of ponderosa pine is from Critchfield and Little.
Before the distinctions between the North Plateau and Pacific races were fully documented, most botanists assumed that ponderosa pines in both areas were the same. In 1948, when a botanist and a geneticist from California found a distinct tree on Mt. Rose in western Nevada with some marked differences from the ponderosa pine they knew in California, they described it as a new species, Washoe pine Pinus washoensis. Subsequent research determined this to be one of the southernmost outliers of the typical North Plateau race of ponderosa pine.
An additional variety, tentatively named P. p. var. willamettensis, found in the Willamette Valley in western Oregon, is rare.
Distinguishing subspecies
The subspecies of
P. ponderosa can be distinguished by measurements along several dimensions:
|
|
|
| Years needles remain green | 3.9±0.25, N=30 | 4.7±0.14, N=50 | 5.7±0.28, N=23 | 4.3±0.18, N=24 | 4.7±0.18, N=5 |
| Foliage length on branch (cm) | 25.1±2.4, N=30 | 26.2±2.2, N=50 | 21.1±1.7, N=23 | 21.8±2.7, N=24 | 42.2±6.7, N=5 |
| Needle length (cm) | 19.8±0.44, N=30 | 16.8±0.29, N=48 | 11.2±0.27, N=23 | 14.7±0.45, N=24 | 15.6±0.57, N=5 |
| Needles per fascicle | 3.0±0.00, N=30 | 3.0±0.00, N=48 | 2.6±0.06, N=23 | 3.0±0.03, N=24 | 2.4±0.11, N=5 |
| Needle thickness | 45.9±0.49, N=30 | 47.8±0.51, N=48 | 46.4±0.68, N=23 | 44.8±0.87, N=24 | 49.7±0.61, N=5 |
| Branches per whorl | 4.4±0.13, N=30 | 3.7±0.11, N=50 | 3.0±0.17, N=23 | 3.4±0.25, N=23 | 2.3±0.11, N=5 |
| Branch angle (° from vertical) | 56±1.8, N=30 | 51±1.7, N=50 | 50±2.3, N=23 | 48±3.1, N=24 | 36±1.9, N=5 |
| Seed cones length (mm) | 101.4±2.48, N=25 | 88.7±1.24, N=36 | 70.7±2.20, N=22 | 74.9±2.51, N=20 | 71.1±2.46, N=5 |
| Seed cones width (mm) | 77.1±1.35, N=25 | 71.6±0.73, N=36 | 61.5±1.08, N=22 | 62.6±1.77, N=20 | 63.3±2.18, N=5 |
| Seed cone form W/L | 0.80±0.03, N=25 | 0.84±0.03, N=36 | 0.90±0.02, N=22 | 0.86±0.02, N=20 | 0.90±0.03, N=5 |
| Seed length (mm) | 7.5±0.08, N=23 | 7.6±0.16, N=14 | 6.3±0.09, N=17 | 6.4±0.18, N=16 | 7.0±0.12, N=5 |
| Seed width (mm) | 4.9±0.05, N=23 | 4.9±0.08, N=14 | 4.1±0.05, N=17 | 4.3±0.09, N=16 | 4.5±0.10, N=5 |
| Seed + wing length (mm) | 32.3±0.58, N=23 | 24.8±0.62, N=14 | 22.9±0.63, N=17 | 23.3±0.68, N=15 | 23.1±0.78, N=5 |
Mature cone color[Smith, R. H. (1981). "Variation in cone color of immature ponderosa pine (Pinaceae) in northern California and southern Oregon". Madroño 28: 272–275.] | apple green to yellow green | green & red-brown to dark purple | green & red-brown to dark purple | | green & red-brown to dark purple |
|
Notes
Names of taxa and transition zones are on the map.
Numbers in columns were derived from multiple measurements of samples taken from 10 (infrequently fewer) trees on a varying number of geographically dispersed plots.
Numbers in each cell show calculated mean ± standard error and number of plots.
Distribution
Pinus ponderosa is a dominant tree in the Kuchler plant association, the ponderosa shrub forest. Like most western pines, the ponderosa is generally associated with mountainous topography. However, it is found on banks of the
Niobrara River in Nebraska. Scattered stands occur in the Willamette Valley of Oregon and in the
Okanagan Valley and
Puget Sound areas of Washington. Stands occur throughout low level valleys in British Columbia reaching as far north as the Thompson, Fraser and Columbia watersheds. In its Northern limits, it grows only below elevation, but is most common below . Ponderosa covers , or 80%,
of the
Black Hills of
South Dakota. It is found on foothills and mid-height peaks of the northern, central, and southern
Rocky Mountains, in the
Cascade Range, in the Sierra Nevada, and in the maritime-influenced Coast Range. In
Arizona, it predominates on the
Mogollon Rim and is scattered on the
Mogollon Plateau and on mid-height peaks () in Arizona and
New Mexico.
Arizona pine (
P. arizonica), found primarily in the mountains of extreme southwestern New Mexico, southeastern Arizona, and northern Mexico and sometimes classified as a variety of ponderosa pine, is presently recognized as a separate species.
Ponderosa pine are also found in the
Chisos Mountains,
Davis Mountains, and Guadalupe Mountains of
Texas, at elevations between .
Ecology
The
fire cycle for ponderosa pine is 5 to 10 years, in which a natural ignition sparks a low-intensity fire.
Low, once-a-decade fires are known to have helped specimens live for half a millennium or more.
The tree has thick bark, and its buds are protected by needles, allowing even some younger individuals to survive weaker fires.
In addition to being adapted to dry, fire-affected areas, the species often appears on the edges of deserts as it is comparatively drought resistant, partly due to the ability to close its leaf pores.
It can also draw some of its water from sandy soils.
Despite being relatively widespread in the American West, it is
Shade tolerance.
Pinus ponderosa needles are the only known food of the of the Gelechiidae moth Chionodes retiniella.
Various animals nest in the ponderosa pines, such as the pileated woodpecker.
Pathology
Pinus ponderosa is affected by
Armillaria,
Phaeolus schweinitzii,
Fomes,
Atropellis canker,
dwarf mistletoe,
Polyporus anceps,
Verticicladiella,
Elytroderma needle cast, and western gall rust.
As an invasive species
Pinus ponderosa is classed as a "
Wilding conifer" and spreads as an
invasive species throughout the high country of New Zealand, where it is beginning to take over, causing the native species of plants not to be able to grow in those locations.
It is also considered a "weed" in parts of Australia.
Uses
Native Americans consumed the seeds and sweet inner bark. They chewed the dried pitch, which was also used as a salve. They used the limbs and branches as firewood and building material, and the trunks were carved into canoes. The needles and roots were made into baskets. The needles were also boiled into a solution to treat coughs and fevers.
Commercial Uses
Ponderosa pine has long been an important commercial timber species in western North America, valued for its versatile wood. In both the United States and Canada (primarily British Columbia), ponderosa pine forests have been harvested for lumber and other wood products since the 19th century.
[David P. Lowery. Ponderosa Pine: An American Wood. Forest Service, United States Department of Agriculture. Ponderosa Pine PDF][Government of British Columbia. Ponderosa Pine. January 25, 2024. Website] Old-growth trees were widely used by settlers as lumber, including for railroads. The wood is pale yellow to light brown, straight-grained, and moderately soft, making it suitable for a wide range of applications in construction and manufacturing.
[Western Wood Products Association. Ponderosa Pine. PDF] Younger trees are of poor quality for lumber due to the tendency to warp.
Structural lumber
Ponderosa pine is extensively used as dimensional lumber in light construction. Its timber is easily milled and was one of the first western woods shipped in quantity to eastern markets in the early 20th century.
Common construction uses have included framing (studs and joists), roof decking, and sheathing in houses where only moderate strength is required.
By the mid-20th century, annual production of ponderosa pine lumber was very high; for example, harvests exceeded 3 billion board feet per year by the late 1930s and peaked at over 4 billion board feet in 1941.
In addition to sawtimber, ponderosa pine is used in round log form for various purposes. The straight trunks were historically sought for utility poles and fence posts; when properly dried or treated, the wood has fair durability in these uses.[United States Department of Agriculture. Ponderosa Pine, Species Review. 2018. PDF]
Blue stained pine
Blue-stained pine is wood marked by blue-gray streaks caused by fungi spread by the mountain pine beetle (Dendroctonus ponderosae). As the beetles infest trees like ponderosa and lodgepole pine, they introduce blue-stain fungi (Grosmannia spp.), which colonize the sapwood but do not weaken the wood structurally. Although often discounted in the marketplace due to its appearance, blue-stained pine is gaining popularity in sustainable and rustic design, where its distinct color is embraced as a natural and decorative feature.
Engineered Wood and Paper Products
Ponderosa pine is widely used in the production of engineered wood and pulp products. A large share of harvested logs goes into plywood, particleboard, fiberboard, and paper.
[David P. Lowery. Ponderosa Pine: An American Wood. Forest Service, United States Department of Agriculture. Ponderosa Pine PDF] Ponderosa pine peeler logs are rotary-cut to produce veneer, which is used in plywood panels.
Although it is less strong than Douglas-fir plywood, it meets the requirements for many light-duty structural and non-structural applications, including furniture panels and drawer bottoms.
[United States Department of Agriculture. Plant Fact Sheet: Ponderosa Pine (Pinus ponderosa P. & C. Lawson). PDF] The wood’s light color and pleasant pine scent add to its appeal for interior use.
Notable uses and structures
Because of its abundance and warm appearance, ponderosa pine has been used in many notable western U.S. buildings, often contributing to a rustic,
parkitecture aesthetic. One iconic example is the Grand Canyon Lodge where architect Gilbert Stanley Underwood used massive ponderosa beams for the sloped roof and expansive interiors.
[National Register of Historic Places. Inventory – Nomination Form: Grand Canyon Lodge. National Archives Catalog] Another example is
Fuller Lodge in Los Alamos, New Mexico, using more than 700 locally harvested ponderosa logs in its log-style design.
[National Park Service. Fuller Lodge – Manhattan Project National Historical Park. National Park Service]
Cultivation
Cultivated as a
bonsai, ponderosas are prized for their rough, flaky bark, contorted trunks, flexible limbs, and dramatic deadwood. Collected specimens can be wildly sculpted by their environment, resulting in beautiful twisted trunks, limbs and deadwood. In the mountains they can be found growing in pockets in the rock, stunting their growth. The main challenge for this species in bonsai cultivation is the natural long length of its needles, which takes years of training and care to reduce.
This species is grown as an ornamental plant in parks and large gardens.
In nuclear testing
During Operation Upshot–Knothole in 1953, a nuclear test was performed in which 145 ponderosa pines were cut down by the United States Forest Service and transported to Area 5 of the Nevada Test Site, where they were planted into the ground and exposed to a nuclear blast to see what the blast wave would do to a forest. The trees were partially burned and blown over.
Culture
Pinus ponderosa is the official state tree of Montana. In a 1908 poll to determine the state tree, Montana schoolchildren chose the tree over the Douglas fir, American larch, and cottonwood. However, the tree was not officially named the state tree until 1949.
The Ponderosa Ranch in the classic TV series Bonanza was named after the ponderosa pine, commonly found in the Lake Tahoe region where the fictional Cartwright family's ranch was set. Bonanza was one of the first Westerns to be filmed in color and made frequent visual use of scenic pine forests to emphasize the ranch’s size and frontier beauty.[Northwest Conifer Connections. "Focus on Ponderosa Pine."
]
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See also
General references
External links
