Vigorously twining herbaceous vine, from massive underground
tuber. Stems to 10 m (30 ft) or more in length, freely branching above; internodes square
in cross section, with corners compressed into “wings,” these often red-purple tinged.
Aerial tubers (bulbils) formed in leaf axils (not as freely as in D. bulbifera), elongate, to
10 cm (4 in) x 3 cm (1.2 in), with rough, bumpy surfaces. Leaves long petioled, opposite
(often with only 1 leaf persistent); blades to 20 cm (8 in) or more long, narrowly heart
shaped, with basal lobes often angular. Flowers small, occasional, male and female arising
from leaf axils on separate plants (i.e., a dioecious species), male flowers in panicles to 30
cm (1 ft) long, female flowers in smaller spikes. Fruit a 3-parted capsule; seeds winged.

NOTE: May be confused with D. bulbifera L., which has small or absent underground
tubers, more numerous aerial tubers, and alternate leaves (see next pages). Native wild
yams, D. floridana Bartl. and D. quarternata (Walt.) Gmel., infrequent in hammocks and
floodplains of north and west Florida, never forming aerial tubers, leaf blades rarely to 15
cm (6 in) long.

=https://www.fleppc.org/ID_book/Dioscorea%20alata.pdf


Dioscorea alata is slender creeping vine reaching a length of several meters. The leaf-stalk slightly purple at both points of attachment. Tubers are usually bright lavender in color, occasionally white. Root is tumorous, often with small axillary tubers.

=http://www.stuartxchange.org/Ubi

Major cultivated species
and most widely distributed throughout the tropics.

=Understanding the genetic diversity and population structure of yam (Dioscorea
alata L.) using microsatellite markers

Distribution: Cultivated throughout the tropics for its edible underground tuber, and unknown in the wild state (Coursey 1967, Purseglove 1975). In Florida, herbarium records now reported for naturalized populations in 7 counties: Escambia, Gadsden, Leon, Levy, Charlotte, Lee, and Dade (Wunderlin et al. 1996).

=https://www.fleppc.org/ID_book/Dioscorea%20alata.pdf


- Throughout the Philippines in thickets at low and medium altitudes.
- Cultivated.
=http://www.stuartxchange.org/Ubi

Life History: Normally grows for 8-10 months, then goes dormant for 3-4 months, with
aerial stems dying back during dormancy (Martin and Rhodes 1977). Grown commercially
as far north as southern Japan, a latitude similar to south Georgia’s (Okagami
1986). Said to survive winters in France if planted deep enough (Coursey 1967). Fertile
seeds rarely produced; spread by aerial tubers and fragments of underground tuber
(Coursey 1967).


=https://www.fleppc.org/ID_book/Dioscorea%20alata.pdf