Cycad trees

Cyasin, a component of the nut of the cycad tree, a native of tropical environs, produces an acute toxicity in addition to drastically increasing the incidence of Lou Gerhig s disease (amyotropic lateral sclerosis). Cyasin is carcinogenic (102). 

Toxic component of badly prepared starch from nuts of the cycad tree. Paralysis arms and legs similar to amyotrophic lateral sclerosis. Death in 5 years. Also carcinogenic. Possible cause of dementia on the Pacific Island of Guam. 

As I continue through the beds, pulling weeds, I recall a trip I took with a friend to Oaxaca, Mexico. We traveled through rainforests rich with diversity of tree ferns, cycads, pipers, aroids, bromeliads, and orchids. We also traveled through small villages where farmers practiced subsistence agriculture. They cultivated a diversity of modern corn varieties, as well as traditional landraces—crops selected for their adaptations to specific locations and their culinary characteristics. Often landraces... 

The flora that has been preserved in the Beacon Supergroup of the Transantarctic Mountains and in Australia, South Africa, India, and South America contain leaves of Glossopteris, Gangamopteris, and Dicroidium, as well as gymnospermous trees (Meyer-Berthaud and Taylor 1989), cycads, ferns, and palyno-morphs (pollen, spores, and acritarchs). The fossilized remains of these plants occur primarily in the Buckley, Fremouw, and Falla formations. 

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