Several good reference works are available to help answer your question.
In the Northeast, you can utilize the following Web site from Cornell University that lists poisonous plants by common name: http://www.ansci.cornell.edu/plants/comlist.html.
Also, Purdue University has a Web site on poisonous plants by animal species at http://vet.purdue.edu/depts/addl/toxic/byanim.htm.
An excellent state-specific reference book on toxic ornamental plants is Toxic Plants of Texas. It discusses the more significant plants. If this book does not answer your question, you can contact the Texas Veterinary Medical Diagnostic Lab (TVMDL) at 979-845-3414. You can also go to the Web site http://texnat.tamu.edu/cmplants/toxic/index.htm.
