Some plants, which in most points of their structure are monocotyledonous, yet have reticulated venation; as in Smilax and Dioscorea.
The following purely Caucasian species also grow on the coastfive species of spearwort, three of saxifrage, Aster caucasica, Dioscorea caucasica, Echinops raddeanus, Hedera colchica, Helleborus caucasica and Peucedanum caucasicum.
In Ghana, farmers plant up to 54 different varieties of climbing yams (Dioscorea spp.) inside the forest to protect the vegetables.
The Mexican wild yam (Dioscorea villosa) contains a substance that may be converted to progesterone in the body.