I raised three katydids this summer. Two are S. furcata, a female and a male (not yet an adult), and this male is S. fasciata (I often hear S. septentrionalis calling at night in July, but have yet to capture one). They find their way to our sweet basil every year as first or second instar nymphs and I take a few in and raise them. After a few years of experimenting, I've found that their favorite foods are sweet basil, spinach, lambsquarters, apples, blackberry (fruit), and petunia flowers. This year I was as thorough as possible documenting their growth, to provide images of each instar for these species which can appear very much alike. Most of the photos are within a few days of each molt. Additionally, I filmed them at each instar, so if other angles are desired I can find them.
The other photos have additional commentary- on that of the adult I discuss possible diagnostic characteristics.
I'm not a katydid expert, but I feel that I've become familiar with these two species over the years, enough to put them in the right place in the Guide! If an expert does feel I've misidentified this individual or the others I've raised, please let me know; I'm just an amateur in the learning process!