Populus deltoides subsp. wislizeni

(S. Watson) Eckenwalder

J. Arnold Arbor. 58: 205. 1977.

Common names: Rio Grande cottonwood álamillo
Basionym: Populus fremontii var. wislizeni S. Watson Amer. J. Sci. Arts, ser. 3, 15: 136. 1878 (as fremonti)
Synonyms: Populus wislizeni (S. Watson) Sargent
Treatment appears in FNA Volume 7. Treatment on page 19. Mentioned on page 17, 18.

Plants to 35 m, usually less than 20 m. Winter buds pubescent, hairs relatively short, stiff. Leaves: blade base with 0 basilaminar glands, apex short-acuminate, abaxial surface glabrous at emergence; preformed blade with (3–) 5–10 teeth on each side; neoformed blade lengths usually less than widths. Pedicels: lengths uniform, (5–) 8–12 (–15 in fruit) mm. Capsules with thick, stiff valves.


Phenology: Flowering Mar–May; fruiting May–Jul.
Habitat: Floodplains, permanent streams, near springs, usually in moist soil, often planted near ranches, irrigation ditches, in towns
Elevation: 1000-2300 m

Distribution

V7 10-distribution-map.gif

Ariz., Colo., N.Mex., Tex., Utah, Wyo., Mexico (Chihuahua)

Discussion

Subspecies wislizeni is the common cottonwood of the Rio Grande and Colorado Plateau regions, where it forms relatively small, scattered groves. It is a fairly homogeneous and distinctive southwestern part of the species. It intergrades with subsp. monilifera on the eastern and northern margins of its range. Populus sargentii Dode var. texana Correll is based upon such intergrades.

Selected References

None.

Lower Taxa

None.
at right angle;plane +
short-acuminate +
James E. Eckenwalder +
(S. Watson) Eckenwalder +
light-brown +
truncate +  and cordate or broadly cuneate +
tubular +  and round +
Populus fremontii var. wislizeni +
9 cm90 mm <br />0.09 m <br /> (14 cm140 mm <br />0.14 m <br />) +
9 cm90 mm <br />0.09 m <br /> (16.5 cm165 mm <br />0.165 m <br />) +
3 cm30 mm <br />0.03 m <br /> (9 cm90 mm <br />0.09 m <br />) +
usually less than widths +
broadly-triangular-ovate +
3 cm30 mm <br />0.03 m <br /> (9 cm90 mm <br />0.09 m <br />) +
deciduous +
0.2 cm2 mm <br />0.002 m <br /> (0.35 cm3.5 mm <br />0.0035 m <br />) +
long-hairy +  and glabrous +
not +  and coarse +
5-angled +  and round +
2 cm20 mm <br />0.02 m <br /> (2.8 cm28 mm <br />0.028 m <br />) +
resinous +
greenish yellow +
flowering +
pubescent +
1.4 cm14 mm <br />0.014 m <br /> (2 cm20 mm <br />0.02 m <br />) +
1.1 cm11 mm <br />0.011 m <br /> (1.6 cm16 mm <br />0.016 m <br />) +
0.8 cm8 mm <br />0.008 m <br /> (1.1 cm11 mm <br />0.011 m <br />) +
(3-)15-40(-55)-flowered +
0.7 cm7 mm <br />0.007 m <br /> (5 cm50 mm <br />0.05 m <br />) +
5 cm50 mm <br />0.05 m <br /> (18 cm180 mm <br />0.18 m <br />) +
Rio Grande cottonwood +  and álamillo +
saucer--shaped +
0.1 cm1 mm <br />0.001 m <br /> (0.3 cm3 mm <br />0.003 m <br />) +
saucer--shaped +
Ariz. +, Colo. +, N.Mex. +, Tex. +, Utah +, Wyo. +  and Mexico (Chihuahua) +
1000-2300 m +
pistillate +  and staminate +
bisexual +  and unisexual +
Floodplains, permanent streams, near springs, usually in moist soil, often planted near ranches, irrigation ditches, in towns +
unbranched +  and spicate +
terminal +  and axillary +
arranged +  and alternate +
marcescent +
deciduous +
0.5 cm5 mm <br />0.005 m <br /> (0.8 cm8 mm <br />0.008 m <br />) +
0.8 cm8 mm <br />0.008 m <br /> (1.2 cm12 mm <br />0.012 m <br />) +
8 cm80 mm <br />0.08 m <br /> (13 cm130 mm <br />0.13 m <br />) +
flattened +
3 cm30 mm <br />0.03 m <br /> (8 cm80 mm <br />0.08 m <br />) +
Flowering Mar–May +  and fruiting May–Jul. +
J. Arnold Arbor. +
0.15 cm1.5 mm <br />0.0015 m <br /> (0.3 cm3 mm <br />0.003 m <br />) +
0.05 cm0.5 mm <br />5.0e-4 m <br /> (0.15 cm1.5 mm <br />0.0015 m <br />) +
Weedy +  and Illustrated +
branched +, sympodial +, monopodial +  and branching +
erect;pendent +
glabrescent;pubescent +
plate-like +
distinct +
persistent +  and deciduous +
grayish green +  and bright green +
Populus wislizeni +
Populus deltoides subsp. wislizeni +
Populus deltoides +
subspecies +
1.5 cm15 mm <br />0.015 m <br /> (2.1 cm21 mm <br />0.021 m <br />) +
0.8 cm8 mm <br />0.008 m <br /> (1.5 cm15 mm <br />0.015 m <br />) +
35 cm350 mm <br />0.35 m <br /> (?) +