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piñón, single leaf pinyon, single-leaf pine, singleleaf pinyon pine

slash pine

Habit Trees to 14m; trunk to 0.5m diam., strongly tapering, much branched; crown usually rounded, dense. Trees to 30m; trunk to 0.8m diam., straight to contorted; crown conic, becoming rounded or flattened.
Bark

red-brown, irregularly furrowed or cross-checked, scaly.

orange- to purple-brown, irregularly furrowed and cross-checked into large, irregularly rectangular, papery-scaly plates.

Branches

spreading and ascending, persistent to near trunk base;

twigs stout, orange-brown, aging brown to gray, sometimes sparsely puberulent.

spreading to ascending;

twigs stout (to ca. 1cm thick), orange-brown, aging darker brown, rough-scaly.

Buds

ellipsoid, light red-brown, 0.5–0.7cm, resinous;

scale margins fringed.

cylindric, silvery brown, 1.5–2cm;

scale margins fringed.

Leaves

1(–2) per fascicle, ascending, persisting 4–6(–10) years, 2–6cm × 1.3–2(–2.5)mm, curved, terete (though often 2-grooved), gray-green, all surfaces with stomatal lines, margins entire, apex subulate;

sheath 0.5–1cm, scales soon recurved, forming rosette, shed early.

2 or 3 per fascicle, spreading or ascending, persisting ca. 2 years, 15–20(–23)cm × 1.2–1.5mm, straight, slightly twisted, pliant, yellow- to blue-green, all surfaces with stomatal lines, margins finely serrulate, apex abruptly acute to acuminate;

sheath 1–2cm, base persistent.

Pollen cones

ellipsoid, ca. 10mm, yellow.

cylindric, 30–40mm, purplish.

Seed(s)

cones maturing in 2 years, shedding seeds and falling soon thereafter, spreading, symmetric, ovoid before opening, broadly depressed-ovoid to nearly globose when open, 4–6(–8)cm, pale yellow-brown, nearly sessile;

apophyses thickened, slightly raised;

umbo subcentral, raised or depressed, nearly truncate, apiculate.

cones maturing in 2 years, falling the year after seed-shed, single or in pairs, symmetric, lance-ovoid before opening, ovoid or ovoid-cylindric when open, (7–)9–18(–20)cm, light chocolate brown, on stalks to 3cm;

apophyses lustrous (as if varnished), slightly raised, strongly cross-keeled;

umbo central, depressed-pyramidal, with short, stout prickle.

2n

=24.

Pinus monophylla

Pinus elliottii

Habitat Dry low-montane or foothill pinyon-juniper woodland
Elevation 1000–2300m (3300–7500ft)
Distribution
from FNA
AZ; CA; ID; NV; UT; Mexico in Baja California
[WildflowerSearch map]
[BONAP county map]
from FNA
AL; FL; GA; LA; MS; SC [Introduced in subtropical and warm temperate areas worldwide]
[WildflowerSearch map]
[BONAP county map]
Discussion

Pinus monophylla hybridizes with P. edulis and P. quadrifolia.

Singleleaf pinyon (Pinus monophylla) is the state tree of Nevada.

(Discussion copyrighted by Flora of North America; reprinted with permission.)

Varieties 2 (native only in the flora).

(Discussion copyrighted by Flora of North America; reprinted with permission.)

Key
1. Seedlings essentially without grass stage, buds thus scattered on the stem; leaves mostly in 3s, sometimes in 2s on same shoot; resin canals 3-5 per leaf; base of open cone ± truncate.
var. elliottii
1. Seedlings tending toward a grass stage, buds thus crowded on contracted stems; leaves mostly in 2s, sometimes in 3s on same shoot; resin canals 3-9 per leaf; base of open cone rounded.
var. densa
Source FNA vol. 2. FNA vol. 2.
Parent taxa Pinaceae > Pinus Pinaceae > Pinus
Sibling taxa
P. albicaulis, P. aristata, P. attenuata, P. balfouriana, P. banksiana, P. cembroides, P. clausa, P. contorta, P. coulteri, P. echinata, P. edulis, P. elliottii, P. engelmannii, P. flexilis, P. glabra, P. jeffreyi, P. lambertiana, P. leiophylla, P. longaeva, P. monticola, P. muricata, P. palustris, P. ponderosa, P. pungens, P. quadrifolia, P. radiata, P. resinosa, P. rigida, P. sabiniana, P. serotina, P. strobiformis, P. strobus, P. sylvestris, P. taeda, P. torreyana, P. virginiana, P. washoensis
P. albicaulis, P. aristata, P. attenuata, P. balfouriana, P. banksiana, P. cembroides, P. clausa, P. contorta, P. coulteri, P. echinata, P. edulis, P. engelmannii, P. flexilis, P. glabra, P. jeffreyi, P. lambertiana, P. leiophylla, P. longaeva, P. monophylla, P. monticola, P. muricata, P. palustris, P. ponderosa, P. pungens, P. quadrifolia, P. radiata, P. resinosa, P. rigida, P. sabiniana, P. serotina, P. strobiformis, P. strobus, P. sylvestris, P. taeda, P. torreyana, P. virginiana, P. washoensis
Subordinate taxa
P. elliottii var. densa, P. elliottii var. elliottii
Synonyms Caryopitys monophylla, P. californiarum, P. cembroides var. monophylla P. heterophylla, P. taeda var. heterophylla
Name authority Torrey & Frémont: in Frémont, Rep. Exped. Rocky Mts. 2: 319, plate 4. (1845) Engelmann: Trans. Acad. Sci. St. Louis 4: 186, plates 1–3. (1880)
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