SEARCH HINT for TOXICITY
Unless you know exactly what Toxicity level the Author thinks that the plant might have, then it is best to leave the TOXICITY set to [Unspecified].
(Toxicity level is mainly an informational parameter rather than one on which to base a search. If the Author doesn't know if the plant is toxic, he has left the toxicity blank, rather than put it at 'lowish'. i.e. The 'Lowish' rating is not the default setting for a plant that is non-toxic. Also, under certain circumstances, even edible plants can be deadly toxic - such as green potatoes!).
Alternatively, if you really would like to know which plants the Author thinks have a, for instance, 'severe' toxicity rating, then click on toxicity?severe and a list will be produced.