| I mistated the number of toxic plants in the Anacardiaceae family. Sorry. It's a case of remembering the right number but the wrong term. The Anacardiaceae does include over 600 species. There are 76 genera of which 25 contain poisonous species. Here is a link to a technical paper (Secondary Compunds Within the Anacardiaceae) which discusses various poisonous genera and the nature of the secondary compounds (ie urushiol oil) which cause dermatitis.
Toxicodendron radicans (poison ivy) used to called Rhus radicans and was considered part of the Rhus genus until about mid 1900's. By placing the poisonous plants such as poison oak and poison ivy in this new genus, the name would better describe the characteristics of the plants. The African sumac is Rhus lancea - still part of the Rhus genus which contains only non-poisonous species. Poison oak is now Toxicodendron diversilobum (western poison oak) or Toxicodendron pubescens (Atlantic or eastern poison oak). |
