Pinus jeffreyi |
Pinaceae |
|||||||||||||||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Jeffrey pine |
pine family |
|||||||||||||||||||||||||
Habit | Trees to 61m; trunk to 2.5m diam., usually straight; crown conic to rounded. | Trees (occasionally shrubs), evergreen (annually deciduous in Larix), resinous and aromatic, monoecious. | ||||||||||||||||||||||||
Roots | fibrous to woody, unspecialized. |
|||||||||||||||||||||||||
Bark | yellow-brown to cinnamon, deeply furrowed and cross-checked, forming large irregular scaly plates. |
smooth to scaly or furrowed. |
||||||||||||||||||||||||
Branches | spreading-ascending; twigs stout (to 2cm thick), purple-brown, often glaucous, aging rough. |
|||||||||||||||||||||||||
Lateral branches | well developed and similar to leading (long) shoots or reduced to well-defined short (spur) shoots (Pinus, Larix); twigs terete, sometimes clothed by persistent primary leaves or leaf bases; longest internodes less than 1cm; buds conspicuous. |
|||||||||||||||||||||||||
Buds | ovoid, tan to pale red-brown, 2–3cm, not resinous; scale margins conspicuously fringed. |
|||||||||||||||||||||||||
Leaves | 3 per fascicle, spreading-ascending, persisting (2–)4–6(–7) years, 12–22(–25)cm × ca. 1.5–2mm, slightly twisted, gray- to yellow-green, all surfaces with fine stomatal lines, margins finely serrulate, apex acute to acuminate; sheath (1–)1.5–2.5(–3)cm, base persistent. |
(needles) simple, shed singly (except whole fascicles shed in Pinus), alternate and spirally arranged but sometimes proximally twisted so as to appear 1- or 2-ranked, or fascicled, linear to needlelike, sessile to short-petiolate; foliage leaves either borne singly (spirally) on long shoots or in tufts (fascicles) on short shoots; juvenile leaves (when present) borne on long shoots, scalelike; resin canals present. |
||||||||||||||||||||||||
Pollen cones | lance-cylindric, 20–35mm, yellow to yellow- or purple-brown or yellow. |
maturing and shed annually, solitary or clustered, axillary, ovoid to ellipsoid or cylindric; sporophylls overlapping, bearing 2 abaxial microsporangia (pollen sacs); pollen spheric, 2-winged, less commonly with wings reduced to frill (in Tsuga sect. Tsuga), or not winged (in Larix and Pseudotsuga). |
||||||||||||||||||||||||
Seed(s) | cones maturing in 2 years, shedding seeds and falling soon thereafter, nearly terminal, spreading, slightly asymmetric at base, ovoid-conic before opening, cylindro-ovoid when open, (10–)15–30cm, light red-brown, nearly sessile or on stalks to 0.5cm, abaxial surface of scales not darker than or sharply contrasting in color with adaxial surface, scales in low spirals (as compared to Pinus ponderosa) of 8 or more per row as viewed from side, those of cones just prior to and after cone fall not so spreading and deflexed, thus not so much separated from adjacent scales; apophyses slightly thickened and raised, not keeled; umbo central, slightly raised, with short, slender, reflexed prickle. |
cones maturing and shed in 1–3 seasons or long-persistent, sometimes serotinous (not opening upon maturity but much later: Pinus), compound, axillary, solitary or grouped; scales overlapping, free from subtending included or exserted bracts for most of length, spirally arranged, strongly flattened, at maturity relatively thin to strongly thickened and woody (in Pinus), with 2 inverted, adaxial ovules. |
||||||||||||||||||||||||
2n | =24. |
|||||||||||||||||||||||||
Pinus jeffreyi |
Pinaceae |
|||||||||||||||||||||||||
Habitat | High, dry montane forests mostly above the Pinus ponderosa zone | |||||||||||||||||||||||||
Elevation | 2000–2500m (6600–8200ft) | |||||||||||||||||||||||||
Distribution |
CA; NV; OR; Mexico in Baja California
|
Almost entirely in the Northern Hemisphere |
||||||||||||||||||||||||
Discussion | Pinus jeffreyi has a form very similar to that of P. ponderosa, but it is a smaller species when compared with sympatric populations of the latter. It is cut and sold under the same name as P. ponderosa, but the sweetish odor of the fresh-cut wood contrasts sharply with the turpentine odor of ponderosa pine. The resin chemistry of the two species is significantly different. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
The Pinaceae, with a fossil record extending back to the Cretaceous (C.N. Miller Jr. 1988), constitute a clearly defined natural taxon, the basic delimiting features of which are seen in the mature seed cones: bract-scale complexes consisting of well-developed scales that are free for most of their length from the subtending bracts, two inverted ovules on the adaxial face of each scale, and usually an obvious seed wing that develops from the cone scale. The 10 genera, too, are clearly defined. The cones of certain members of the Pinaceae remain on the tree and closed for several to many years until a stimulus (often fire) causes them to open and shed their seeds. This condition, known as serotiny (adjective, serotinous), is seen in various pines (e.g., Pinus attenuata, P. banksiana, P. contorta). This primarily Northern Hemisphere family extends south to the West Indies, Central America, Japan, China, Indonesia, the Himalayas, and North Africa. The family is dominant in the vegetation of large regions including, in the flora area, forests of the boreal and Pacific regions, of the western mountains, and of the southeastern coastal plain. Only one species of the family, Pinus merkusii, crosses the equator (in Sumatra). Members of the Pinaceae are of major economic importance as producers of most of the world's softwood timber. Additionally, they are sources of pulpwood, naval stores (e.g., tar, pitch, turpentine, etc.), essential oils, and other forest products. All members of the family present in the flora, especially pines, are of varying importance to wildlife for food and cover. Many species, including most of the genera, are grown as ornamentals and shelter-belt trees and for revegetation. Most commonly seen in cultivation in the flora area are species of Abies, Cedrus, Larix, Picea, Pinus, Pseudotsuga, and Tsuga, each of these genera being represented by numerous cultivars. Keteleeria and Pseudolarix are mainly botanical garden subjects. Cathaya, the most recently described genus (1958), is apparently not yet in cultivation in North America. Among the vegetative features useful for identification of some genera of Pinaceae are the leaf scars. These are best observed on those portions of living branchlets from which leaves have fallen. Genera 10, species ca. 200 (6 genera, 66 species in the flora with 64 natives and 2 naturalized). (Discussion copyrighted by Flora of North America; reprinted with permission.) |
||||||||||||||||||||||||
Key |
|
|||||||||||||||||||||||||
Source | FNA vol. 2. | FNA vol. 2, p. 352. | ||||||||||||||||||||||||
Parent taxa | Pinaceae > Pinus | |||||||||||||||||||||||||
Sibling taxa | ||||||||||||||||||||||||||
Subordinate taxa | ||||||||||||||||||||||||||
Synonyms | P. deflexa, P. jeffreyi var. deflexa, P. ponderosa var. jeffreyi | |||||||||||||||||||||||||
Name authority | Greville & Balfour: in A. Murray bis, Bot. Exped. Oregon 8: 2 plates. (1853) | Lindley | ||||||||||||||||||||||||
Web links |
|