Pinus strobus

Trees to 67m; trunk to 1.8m diam., straight; crown conic, becoming rounded to flattened. Bark gray-brown, deeply furrowed, with long, irregularly rectangular, scaly plates. Branches whorled, spreading-upswept; twigs slender, pale red-brown, glabrous or pale puberulent, aging gray, ±smooth. Buds ovoid-cylindric, light red-brown, 0.4--0.5cm, slightly resinous. Leaves 5 per fascicle, spreading to ascending, persisting 2--3 years, 6--10cm ´ 0.7--1mm, straight, slightly twisted, pliant, deep green to blue-green, pale stomatal lines evident only on adaxial surfaces, margins finely serrulate, apex abruptly acute to short-acuminate; sheath 1--1.5cm, shed early. Pollen cones ellipsoid, 10--15mm, yellow. Seed cones maturing in 2 years, shedding seeds and falling soon thereafter, clustered, pendent, symmetric, cylindric to lance-cylindric or ellipsoid-cylindric before opening, ellipsoid-cylindric to cylindric or lance-cylindric when open, (7--)8--20cm, gray-brown to pale brown, with purple or gray tints, stalks 2--3cm; apophyses slightly raised, resinous at tip; umbo terminal, low. Seeds compressed, broadly obliquely obovoid; body 5--6mm, red-brown mottled with black; wing 1.8--2.5cm, pale brown. 2 n =24.

Mesic to dry sites; 0--1500m; St. Pierre and Miquelon; Man., N.B., Nfld., N.S., Ont., P.E.I., Que.; Conn., Del., Ga., Ill., Ind., Iowa, Ky., Maine, Md., Mass., Mich., Minn., N.H., N.J., N.Y., N.C., Pa., Ohio, R.I., S.C., Tenn., Vt., Va., W.Va., Wis.; Mexico; Central America in Guatemala.

Pinus strobus is an important timber tree; because of extensive lumbering, few uncut stands remain. It was once prized as a source for ship masts, and large tracts of it were reserved for the Royal Navy during colonial times.

Pinus strobus var. chiapensis appears to be as Martínez saw it: a clinal variant that, compared to the type variety, has finer leaves, different resin canal distribution, and heavier cones when cones of similar sizes are compared.

Eastern white pine ( Pinus strobus ) is the provincial tree of Ontario and the state tree of Maine and Michigan.

Tree 22 - 30 m tall, sometimes much larger, trunk diameter to 1 m or more Bark: greenish, thin, and smooth on young trees, becoming brownish gray, thick, and fissured into rectangular plates. Twigs: slender, orangish brown, slightly hairy, becoming light brown and hairless with age. Buds: yellowish brown, 0.4 - 1 cm long, egg-shaped to cylindrical, and pointed. Form: pyramidal to broadly oval-shaped with wide-spreading, horizontal branches. Pollen cones: yellow, about 8 mm long, egg-shaped, and clustered at the base of new shoots in the mid-crown. Needles: in clusters of five, pale bluish green, 7 - 12 cm long, sharp-pointed, three-sided with finely toothed edges, straight, thin and flexible. The sheath at the base of each needle cluster is deciduous. Young seed cones: pinkish purple, 0.6 - 1 cm long, cylindrical, at the tips of new shoots in the upper crown. Pollination between cones occurs in June. Mature seed cones: woody, short-stalked, hanging downward, pale brown with a purple or grayish tint, 10 - 25 cm long, and cylindrical. Scales flexible and lacking prickles. Seeds reddish brown, 5 - 8 mm long, narrow-cylindrical, with a wing nearing 2 cm long.

Similar species: Having soft, five-clustered needles is what distinguishes Pinus strobus from all other Pinus species in the Chicago Region, which have either two or three needles per cluster.

Habitat and ecology: Highly variable, from mesic to dry sites, including bogs, moist woods, wooded slopes, and dunes.

Occurence in the Chicago region: native

Notes: Pinus strobus is one of the most generally useful of all American woods. At one time it was the most valuable tree of the Northeast, often used in shipbuilding. Today the wood is used for doors, cabinets, interior finish, lumber, pulp, boxes, matches, and carving. It is planted as an ornamental, but restricted in commercial planting due to the white pine blister rust fungus (Cronartium ribicola) and the white pine weevil (Pissoides strobi).

Etymology: Pinus is the Latin word for pine. Strobus is the Latin word for pinecone.

Author: The Morton Arboretum

Tall tree, to 70 m, with long, irregular branches; bark becoming thick, dark, and furrowed; wood pale, soft, not very resinous; lvs very slender, in 5's, mostly persisting 2 years, pale green and glaucous, 8-13 cm, with 1 fibrovascular bundle; bundle-sheath deciduous; cones commonly borne near the tips of the longer branches, cylindric, often bent, 10-15 cm, the apophysis not thickened, the umbo resinous and terminal, unarmed; seed (wing included) 2-3 cm. Many habitats, esp. in fertile or well drained, sandy soil; Nf. to Minn. and se. Man., s. to Del., n. Ga., Ky., and Io.

Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.

©The New York Botanical Garden. All rights reserved. Used by permission.

From Flora of Indiana (1940) by Charles C. Deam

This species is local and is usually found in limited numbers, except along Bear Creek, Fountain County and Big Pine Creek in Warren County where there were formerly many acres of it. In the dune area it was scattered in its distribution with a large colony here and there. There formerly were several acres of it in a bog east of Merrillville, Lake County, but it has now nearly disappeared. In our area its favored habitat was wet woods or boggy places, on the dunes along Lake Michigan, on cliffs and high banks along Bear Creek, Fountain County, and in a like habitat including adjacent lowland in Warren County along Big Pine and Kickapoo Creeks.

……

Indiana Coefficient of Conservatism: C = 5

Wetland Indicator Status: FACU