Ruta graveolens
In the Feb/March issue of Horticulture magazine they made a beginner’s error. They talked about Rue being a host plant for Black Swallowtails, but then showed a picture of Meadow Rue (Thalictrum), which is nothing like the Rue (Ruta graveolens), Swallowtails are looking for. Make sure you get the right one when you’re at the nursery. Note – rue might give you a rash, but I’ve only had one person tell me that they had a problem with it.
Butterfly Gardening 
We regret the error! The article’s author just told us meadow rue (Thalictrum) is more often used as food by the Giant Swallowtails, but not by the Black Swallowtail, which prefers Ruta graveolens, as you point out.
We misinterpreted his original text.
This points to the value of Latin names. Though many different plants may share the same common name, often depending on region, every plant has a unique Latin name. At Horticulture we try to include the Latin in all our articles; unfortunately we did make an oversight here. Thank you very much for the clarification. We’ll do the same for our readers.