Manihot esculenta
Manihot angustiloba
bitter cassava, cassava, manioc, tapioca
desert-mountain manihot, narrow-leaf cassava, pata de gallo
thickened.
thickened.
erect, terete when young;
nodes conspicuously swollen;
leaf and stipule scars elevated, especially on older stems.
erect, terete when young;
nodes not swollen;
leaf and stipule scars not elevated.
persistent;
stipules lanceolate, entire;
petiole 3–20 cm;
blade basally attached, usually 3–10-lobed, sometimes unlobed, lobes without secondary lobes, median lobe 5–18 cm, margins neither thickened nor revolute, entire to ± repand, apex acuminate, surfaces glabrous or hairy, abaxial finely reticulate.
stipules lanceolate, entire;
petiole 3–12 cm;
blade basally attached, 5–7-lobed, lobes with acute secondary lobes proximally, median lobe 5–15 cm, margins neither thickened nor revolute, remotely serrate, apex acute, surfaces glabrous, abaxial smooth.
axillary, panicles, 2–10 cm.
axillary, racemes, to 12 cm.
staminate 2–4 mm; pistillate 20 mm in fruit, straight.
staminate 3–8 mm; pistillate 10–25 mm in fruit, downcurved.
calyx campanulate, 10–15 mm, lobes erect or spreading;
stamens 10.
calyx campanulate, 10–18 mm, lobes erect or spreading;
stamens 10.
1.5 cm, usually winged.
1.5 cm, finely tuberculate, not winged.
subglobose to oblong, 12 mm.
globose, 12 mm.
= 36.
Manihot esculenta
Manihot angustiloba
The enlarged storage roots of Manihot esculenta yield a starchy staple, now much consumed in tropical regions around the world. Tapioca, a pelletized and partially hydrolyzed form of cassava starch, is the chief form of consumption in temperate regions. Multiple cultivars are known. These are generally characterized as bitter (containing cyanogenic glycosides, which must be removed before consumption) or sweet (cyanogenic glycosides absent or at low levels). A form with variegated leaves is sometimes grown for ornament. Cassava was cultivated throughout the Neotropics in pre-Columbian times. As a root crop with poor storage qualities adapted to humid regions, archeological remains are few, leading to much speculation in the literature about the origin of this important crop. Molecular data reported by K. Olsen and B. A. Schaal (1999, 2001), indicate that cultivated cassava constitutes M. esculenta subsp. esculenta, derived by artificial selection from its sole wild ancestor, M. esculenta subsp. flabellifolia (Pohl) Ciferri from the southern border of the Amazon basin. Under this classification, all North American plants belong to subsp. esculenta.
(Discussion copyrighted by Flora of North America; reprinted with permission.)
D. J. Rogers and S. G. Appan (1973) noted the overall similarity and nearly identical geographic ranges of Manihot angustiloba and M. davisiae, yet they maintained these taxa as separate species, presumably because of their (nearly) constant and consistent differences in leaf lobe outline. Manihot angustiloba has generally narrow, nearly linear, primary lobes with a pair of serrate secondary lobes forming the widest portion of the lobe proximal to the middle; M. davisiae has generally broader leaf lobes with one pair of rounded secondary lobes that form the widest portion of the lobe distal to the middle, or two pairs of nearly equal, rounded, secondary lobes proximal and distal to the middle. Some specimens exhibit an intermediate condition: primary lobes that are narrow distally but also bear a pair of rounded secondary lobes proximal to the middle.
In the flora area, Manihot angustiloba is restricted to Cochise, Pima, and Santa Cruz counties.
(Discussion copyrighted by Flora of North America; reprinted with permission.)
WildflowerSearch
iNaturalist
USDA Plants Database
