Pinus washoensis

H. Mason & Stockwell

Madroño 8: 62. 1945.

Common names: Washoe pine
EndemicConservation concern
Treatment appears in FNA Volume 2.

Trees to 60m; trunk to 1m diam., straight; crown pyramidal. Bark yellowbrown to reddish, fissured, plates scaly. Branches spreading-ascending; twigs stout, orangish, aging gray, rough. Buds ovoid, redbrown, 1.5–2cm, not resinous; scale margins fringed. Leaves (2–) 3 per fascicle, spreading-ascending, persisting (2–) 4–6 (–7) years, 10–15cm × ca. 1.5mm, slightly twisted, gray-green, all surfaces with stomatal lines, margins finely serrulate, apex acuminate; sheath 1–2cm, base persistent. Pollen cones cylindric, 10–20mm, red-purple. Seed-cones maturing in 2 years, shedding seeds soon thereafter, not persistent, spreading, slightly asymmetric, ovoid-conic before opening, broadly ovoid when open, 7–10cm, tan or pale redbrown, sessile, abaxial surface of scales darker and sharply contrasting in color with adaxial surface; apophyses slightly raised, low pyramidal; umbo central, narrowly pyramidal, tapering into short, reflexed, fine prickle. Seeds ellipsoid; body ca. 0.8cm, gray-brown; wing to 16mm. 2n =24.


Habitat: Dry montane forests
Elevation: 2100–2500m

Discussion

Pinus washoensis often occurs in large stands and resembles P. jeffreyi. The number and posture of seed-cone scales fall within the ranges given for P. jeffreyi. The abaxial surface of these scales has a significantly darker pigmentation, however; such a color contrast is not apparent in P. jeffreyi. Forest geneticists have developed hybrids between P. washoensis and related yellow pines, but no natural hybrids have been observed. Some workers regard P. washoensis as closely related to—or even conspecific with--- P. ponderosa.

Of conservation concern.

Selected References

None.

Lower Taxa

None.

"fine" is not a number."relatively thin" is not a number.

... more about "Pinus washoensis"
resinous +
acuminate +
Robert Kral +
H. Mason & Stockwell +
yellowbrown;reddish +
fissured +
persistent +
gray-brown +
0.8 cm8 mm <br />0.008 m <br /> (?) +
spreading-ascending +
not resinous +
conspicuous +
1.5 cm15 mm <br />0.015 m <br /> (2 cm20 mm <br />0.02 m <br />) +
Washoe pine +
pale redbrown;tan +
7 cm70 mm <br />0.07 m <br /> (10 cm100 mm <br />0.1 m <br />) +
not persistent +
ovoid +  and ovoid-conic +
pyramidal +
Calif. +  and Nev. +
2100–2500m +
sheathed +  and sessile +
rounded +, 2-3-angled +  and terete +
Dry montane forests +
arranged +  and fascicles +
gray-green +
persisting +
10 cm100 mm <br />0.1 m <br /> (15 cm150 mm <br />0.15 m <br />) +
spreading-ascending +
4 (?) +  and 6 (?) +
scale-like +
1.5 cm15 mm <br />0.015 m <br /> (?) +
0 cm0 mm <br />0 m <br /> (1 cm10 mm <br />0.01 m <br />) +
not winged +  and 2-winged +
tan +  and yellow red blue or lavender +
1 cm10 mm <br />0.01 m <br /> (2 cm20 mm <br />0.02 m <br />) +
fibrous;woody +
arranged +  and overlapping +
persistent +
flattened +
pliable +  and woody +
grouped +  and solitary +
long-persistent +
wingless +, winged +, stalked +  and sessile +
persistent +
pendent;more or less erect +
ellipsoid +
1 cm10 mm <br />0.01 m <br /> (2 cm20 mm <br />0.02 m <br />) +
reduced;well-defined short +
Endemic +  and Conservation concern +
extended +
Apinus +, Strobus +  and Caryopitys +
Pinus washoensis +
species +
decurrent +  and elongate +
straight +
gray +  and orangish +
tapering +  and pyramidal +
reduced +
0 cm0 mm <br />0 m <br /> (?) +  and 1.6 cm16 mm <br />0.016 m <br /> (?) +