The pink ones are what happens after the flower is pollinated. There is a pink form, 'rosem' but your look like the older, pollinated ones. The red one is T. erectum, it's wierd though cause its only got 4 stamens not 3 0r 6. The two green ones are T. grandiflorum infected with Mycoplasma, a ultra-microscopic membrane that surrounds the conducting tissues. The pics look great.
t

Yes, a beautiful set of photos. They remind me of my walks through the trillium fields of the southern Appalachians. In particular I remember one little valley that was literally covered in T. grandiflorum as far as you could see! Thanks for the photos. PF

Interesting Trilliophile, I had assumed it was a genetic mutation. Is that infected condition permanent? In other words, will those plants remain infected and continue to produce such flowers each year?

Is such an infection dangerous to the plant?

What is the diseases vector? Any idea?

They will stay infected for the rest of their lives. Most likely they will decline slowly and then die. The literature doen't give recomendations other than they should not be moved to other areas of the country. THey believe that leafhoppers spread it around, but no one really knows. There is not much that can be done about the disease other than to enjoy the wierd blooms.
aloha
t