Ponderosa pine (Pinus ponderosa): what the agencies record

This page reports what US federal publications say about one tree. It does not identify trees from descriptions or photos and does not say what should be done with any tree. The family overview, tree species in the agency records, explains the sources and holds the comparison table.

At a glance

Item	What the source records
Scientific name	Pinus ponderosa Dougl. ex Laws., pine family; two varieties, var. ponderosa and var. scopulorum
Other names	Western yellow pine (Silvics); western yellow, bull and blackjack pine (Wood Handbook)
Native status, USDA PLANTS	Native in Canada and in the lower 48 states
Common size, Silvics	Trunk diameters of 76 to 127 cm (30 to 50 in) and heights of 27.4 to 39.6 m (90 to 130 ft) throughout most of the range
Lifespan, Silvics	Trees often reach ages of 300 to 600 years
Green weight of the wood, NRS-38	45 lb per cubic foot, without bark

Native range

The Silvics of North America handbook (Agriculture Handbook 654, volume 1, 1990) calls ponderosa pine one of the most widely distributed pines in western North America, with a range from southern Canada into Mexico and from Nebraska and Oklahoma to the Pacific Coast. It recognizes two varieties. Pacific ponderosa pine (var. ponderosa) ranges from latitude 52 degrees N in the Fraser River drainage of southern British Columbia south through the mountains of Washington, Oregon and California to near San Diego, and east to Montana and the Snake River Plain in Idaho. Rocky Mountain ponderosa pine (var. scopulorum) lies east of the Continental Divide from north-central Montana into the Dakotas, eastern Wyoming and north-central Nebraska, with the most extensive stands in the Black Hills, and south through Colorado, New Mexico, Arizona, western Texas and northwestern Oklahoma into northern Mexico. The handbook says the species is absent from a large area that includes southwestern Montana, western Wyoming, southern Idaho and part of the Great Basin. It says Arizona pine, sometimes classed as a variety, is recognized as a separate species.

Size, age and growth

Silvics says ponderosa pine grows to impressive size, with a recorded stem 263 cm (103.5 in) across and 70.7 m (232 ft) tall. Diameter growth can be rapid and fairly constant when trees have adequate growing space: free-growing trees on productive California sites reached 66 cm (26 in) across by age 30, while in central Oregon trees of 13 to 51 cm (5 to 20 in) grew about 12 cm (4.9 in) per decade if free of competition. The handbook says shrubs and neighbouring trees can restrict diameter growth markedly.

Cones

The handbook describes the species as monoecious. In western Montana, central Idaho and eastern Oregon at 910 to 1830 m (3,000 to 6,000 ft), flowering generally begins between May 1 and 10, pollen is shed May 25 to June 15, cones reach their full size of 8 to 15 cm (3 to 6 in) in July and August of the following year, and seed is shed until November. It says pollen on the west slope of the Sierra Nevada is shed an average of 8 days later for each 300 m (1,000 ft) rise in elevation.

Roots

Silvics says the ability of seedlings to grow vigorous taproots is one reason for their hold on severe sites where associated species often fail. Within a few months of germination roots can penetrate to 50 cm (20 in) or more in loosened, watered soil, and mature trees put down a root more than 2 m (6 ft) deep in porous soils. The handbook ties this rapid root growth to the tree's adaptation to the Southwest, where seed does not germinate until summer rains begin, usually in July.

Wood

The Wood Handbook (FPL-GTR-282, 2021) says Jeffrey pine grows with ponderosa pine in California and Oregon and is usually marketed under the ponderosa name. It names Oregon, Washington and California as the major producing areas, with Idaho and Montana also important. It describes light reddish brown heartwood and wide, nearly white to pale yellow sapwood, with the wood of the outer portions of sawtimber-size trees generally moderately light in weight, moderately low in strength, moderately soft and moderately stiff. It calls the wood generally straight grained, quite uniform in texture, with moderately low shrinkage and little tendency to warp and twist. Uses it lists are lumber, piles, poles, posts, mine timbers, veneer and crossties, with clear wood going into sashes, doors, blinds, molding, paneling and interior woodwork.

Wood Handbook Table 5-3b	Specific gravity	Modulus of rupture (lbf per square inch)	Side hardness (lbf)
Green	0.38	5,100	320
At 12% moisture content	0.40	9,400	460

The Wood Handbook states that specific gravity is based on oven-dry weight and the volume when green or at 12% moisture content. The green weight of the wood without bark is in the NRS-38 table, the same figure used in the log weight calculator.

Pests and diseases the handbook names

Silvics (1990) says at least 108 insect species attack the Pacific variety and 59 the Rocky Mountain variety. It names these agents by the names it used.

Bark beetles. Several Dendroctonus species are called the most damaging tree-killing insects. The western pine beetle is a common cause of mortality in overmature trees from Baja California to Oregon, Washington, Idaho, western Montana and western Canada, and the mountain pine beetle is called the most destructive and aggressive enemy in the central and southern Rocky Mountains. The handbook says it killed between 5.7 and 11 million cubic metres of ponderosa pine in the Black Hills in 1894 to 1908. Ips engraver beetles are second in destructiveness, and the handbook names 11 species on the tree. The guide on mountain pine beetle gives the agencies' current wording.
Bud, shoot and needle feeders. Pine tip moths, a pitch midge, the western pineshoot borer, the pine reproduction weevil, the pine butterfly, the pandora moth and the pine needle sheathminer.
Dwarf mistletoe. Called the tree's most widespread disease, absent only in the Black Hills and said to infect trees on about one-third of the commercial acreage in the Southwest.
Root diseases. Black stain root disease (Leptographium wageneri), Heterobasidion annosum, and Armillaria. The handbook says the first two kill trees of all ages and the resulting group mortality is sometimes mistaken for bark beetle work.
Heart rots and foliage. Western red rot (Dichomitus squalens) in the southern Rockies and Black Hills, Phellinus pini on the Pacific Coast, and a needle cast, Elytroderma deformans, called the most serious foliage disease.
Rusts. Limb rust, western gall rust and comandra blister rust.
Animals. Rabbits, hares, pocket gophers, squirrels, porcupines, deer, sheep and cattle.

Suspected sightings of regulated pests go to the offices on the United States reporting page or the Canada reporting page. Who may apply pesticides is in pesticide licences by country.