I waded through a lot of the different Poisonous Plant lists when I first got a baby tortoise from a friend in 2004, and then again when I got chickens.  Some of the lists were misleading by making no distinctions between a toxic plant that causes rashes and one that will kill my pets if they eat it.

Through my research, I realized I actually grew a large number of plants in my yard that are considered toxic, but I also learned there are varying degrees of toxicity in plants.  My garden would be an all you can eat buffet for the chickens if I only cultivated stuff that was good for them to eat.   Most of the toxic offenders in my backyard generally cause dermatitis or gastric problems (minor toxicity,) but I do have a handful of plants that have major toxicity.  My chickens leave them alone, and if they have taken a nibble over the years, they never bothered them again.  Warning: Hungry chickens will eventually eat almost any plants if there is nothing else green to forage around or no other good food source, even major toxic plants!

Here is a short simple list of major toxic commonly grown plants found in yards around Southern California.  Most of these could cause serious illness or death to the chickens, the dog, or me if I ate them.  It is NOT a complete list of everything toxic planted around SoCal yards, just the more popular stuff.

• Apple (just the seeds)
• Azalea
• Black Locust (seeds)
• Brugmansia sanguinea (Angel’s Trumpet)
• Castor Bean
• Cherry (just the seeds/ pits)
• Chinese lantern
• Coral tree
• Daphne
• Datura stramonium (Jimson Weed)
• Delphinium
• English Yew
• Foxglove
• Ground cherry
• Heather
• Heliotrope
• Hydrangea
• Lantana
• Larkspur
• Loquat (just the seeds)
• Morning Glory (seeds)
• Nectarine (just the seeds/ pits) or any stone fruit pits in the Prunus genus
• Nicotiana glauca (Tree Tobacco)
• Oleander
• pear (just the seeds)/ seeds from the pyrus genus
• Peach (just the seeds/ pits)
• pittosporum
• Plum  (just the seeds/ pits)
• Star-of-Bethelehem
• Vinca

I finally decided to worry only about the really worst offenders that are deadly.  I have kept a watchful eye, and noticed my animals leave all the toxic stuff alone that we grow, and instead they stick to other stuff around the yard, but that might not be the case for everyone’s pets or chickens.

U.C. Agricultural and Natural Resources keeps a good data base of toxic plants and their levels of toxicity. There are more detailed lists and explanations of the different types of toxicity in plants in a downloadable PDF on their website.