Excerpts from Jim Conrad's
Naturalist Newsletter

from the August 22, 2010 Newsletter issued from Hacienda Chichen Resort beside Chichén Itzá Ruins, central Yucatán, MÉXICO

Camote, or sweet potato, IPOMOEA BATATAS

Friday I found Luis busy working in the traditional Maya milpa, or cornfield, planting "camotes" (ka-MOH- tehs), or sweet potatoes. You can see how unlike Maya sweet potatoes are to what we have up North above. In that picture the tubers are upside down, so those are roots on top, and the long thing at the far left is a stem bearing a couple of very small, heart-shaped leaves. Luis said that he'd just buried some tubers much larger than the big one in the picture, and that Maya sweet potatoes come in colors of white, yellow and purple.

The Northern sweet potato is IPOMOEA BATATAS, a member of the Morning-Glory Family, the Convolvulaceae, and this is the same thing, just one of the many variations of that much-cultivated, native tropical American species. In the online Flora de Veracruz, Andrew McDonald describes the species' tubers as white, yellow, orange, purple or red, and ranging in form from turnip-shaped to narrowed on both ends (fusiform). Of the species' complex genetics he writes that it's hexaploid, and that it hybridizes with closely related diploid species forming tetraploids, and that it produces populations exhibiting intermediate morphological features.

Next Luis showed me Jícama beans he'd carried from home in a plastic bag and was about to plant. They're below:

beans of Jícama, or Yam Bean, PACHYRRHIZUS EROSUS

Jícama (HEE-ka-ma) is sometimes referred to in English as Yam Bean. It's PACHYRRHIZUS EROSUS, a member of the Bean Family, native to Mexico and Central America but much planted in the tropics worldwide for its starchy, highly edible tubers.

Next Luis showed me Chayote fruits he'd just planted at the base of a small, dead tree, which later the rampant Chayote vines will climb up. They're shown below:


Chayote is SECHIUM EDULE. I read that in English sometimes it's called Christophine but I've never heard that name. It's a member of the Cucumber Family. In the picture the things looking like sticking-out tongues develop into shoots that form much-branching vines that can completely cover a hut like mine, producing an incredible number of fruits like the ones in the picture. You boil them and they taste a litle like boiled potatoes. Some Chayote varieties bristle with soft spines, but these are the smooth ones. Chayote's tubers also can be eaten.

Finally Luis showed me the Ñame (NYAH-meh) he was about to plant. You can see Luis in his Virgin of Guadalupe cap holding half a rooting Ñame tuber below:

Ñame, or White Yam, or Water Yam, DIOSCOREA ALATA

Ñame is DIOSCOREA ALATA, a member of the Yam Family, the Dioscoreaceae. In English sometimes it's referred to as White Yam or Water Yam. In eastern North America at the beginning of winter often you see slender, frost-bitten vines at woods edges bearing straw-colored, Chinese-lantern affairs. Those vines are usually called Wild Yams, and they're in the same genus as Ñame, Dioscorea. Wild Yam tubers are very hard and small compared to Ñame's. Ñame is thought to be a native of southern Asia. Its tubers can be enormous. When Luis spread his hands to show how wide he expects his yams to grow, they were about two feet apart (60 cm), so we'll just see if he exaggerates much!