Schoenocaulon texanum

Scheele

Linnaea 25: 262. 1852.

Illustrated
Treatment appears in FNA Volume 26. Treatment on page 81. Mentioned on page 75, 80.

Bulbs ellipsoid to plumply ovoid, 2–4.5 × 1.2–4 cm diam., usually arranged either in a circle or semicircle around a common rhizome, or one above the other on a vertical rhizome. Leaves 5–8, 15–60 cm × 2–6 mm, shorter than raceme to just surpassing it, rarely longer. Scape 13.5–55 cm. Racemes condensed, 30–250-flowered, 4–32 cm, flowers closely packed along axis. Flowers: tepals linear to cuneate proximally and broadly subulate distally, 2.3–3.8 mm, fleshy, margins entire or rarely irregularly crenate; auricles distinct or absent; filaments subulate, 2 times tepal length. Capsules 1–3-locular, ellipsoid to plumply ovoid, 0.8–1.9 cm × 5–12 mm. Seeds 2–4 (–8) per locule, 3–6.7 × 1.6–2.2 mm. 2n = 16.


Phenology: Flowering spring–early summer, sometimes later following unseasonable rainfall.
Habitat: Occasional in dry, rocky, limestone soils in chaparrals, usually growing under scrubby vegetation
Elevation: 0–2200 m

Distribution

V26 72-distribution-map.jpg

N.Mex., Tex., Mexico (Chihuahua), Mexico (Coahuila), Mexico (Durango), Mexico (San Luis Potosí)

Discussion

The morphology of Schoenocaulon texanum is peculiarly dependent upon annual rainfall. Plants of small stature but average bulb size can be readily distinguished as the products of one or several seasons of lower than normal rainfall. The hallmarks of such plants are congested racemes, few flowers, these often appearing withered and brown, and ovaries that do not mature or have perhaps only one small locule ripening to produce a few seeds.

Selected References

None.

Lower Taxa

None.

"broad" is not a number."timestepallength" is not declared as a valid unit of measurement for this property.

... more about "Schoenocaulon texanum"
extrose +  and explanate +
cordate +  and linear +
Dawn Frame +
Scheele +
whorled +, opposite +  and alternate +
dilated +
reticulate-veined +  and parallel-veined +
sheathing +  and involucrate +
persistent +
1;several +
membranous +
tunicate +  and scaly +
1.2cm +  and 4cm +
0.8 cm8 mm <br />0.008 m <br /> (1.9 cm19 mm <br />0.019 m <br />) +
ellipsoid +  and plumply ovoid +
0.5 cm5 mm <br />0.005 m <br /> (1.2 cm12 mm <br />0.012 m <br />) +
N.Mex. +, Tex. +, Mexico (Chihuahua) +, Mexico (Coahuila) +, Mexico (Durango) +  and Mexico (San Luis Potosí) +
0–2200 m +
withering-persistent +
sessile +  and pedicellate +
unisexual +  and bisexual +
membranaceous +  and leathery +
Occasional in dry, rocky, limestone soils in chaparrals, usually growing under scrubby vegetation +
persistent +
15 cm150 mm <br />0.15 m <br /> (60 cm600 mm <br />0.6 m <br />) +
0.2 cm2 mm <br />0.002 m <br /> (0.6 cm6 mm <br />0.006 m <br />) +
crenate +  and entire +
many;several +
zygomorphic +  and actinomorphic +
Flowering spring–early summer, sometimes later following unseasonable rainfall. +
30-250-flowered +  and condensed +
spikelike +
4 cm40 mm <br />0.04 m <br /> (32 cm320 mm <br />0.32 m <br />) +
13.5 cm135 mm <br />0.135 m <br /> (55 cm550 mm <br />0.55 m <br />) +
wind-distributed +
0.3 cm3 mm <br />0.003 m <br /> (0.67 cm6.7 mm <br />0.0067 m <br />) +
2 +  and 4 +
ellipsoid +  and ovoid or conic irregularly compressed or angled +
0.16 cm1.6 mm <br />0.0016 m <br /> (?) +  and 0.22 cm2.2 mm <br />0.0022 m <br /> (?) +
Illustrated +
staminodial +
1 +  and several +
persistent +
distinct +
Asagraea +, Sabadilla +  and Skoinolon +
Schoenocaulon texanum +
Schoenocaulon +
species +
greenish purple;green;greenish purple;green;yellowish green +
withering-persistent +
distinct +
subulate +, linear +  and cuneate +
0.23 cm2.3 mm <br />0.0023 m <br /> (0.38 cm3.8 mm <br />0.0038 m <br />) +
sepaloid +  and petaloid +
narrower +
3 +  and 2 +