An escaped ornamental species, growing roadside. I almost didn't add this one to the Field Guide pool -- figured there must be a dozen shots of these in there (big, showy, photogenic, supposedly fairly common roadsides -- although this is the first time I've seen it myself). Nope! Not a one!
Not to be confused with similar native Lilium species such as Lilium pardalinum that are sometimes called Tiger Lilies too. Nor with the similarly colored, erect day lily that I grew up calling Tiger Lily, Hemerocallis fulva.