It sure sounds like a trillium.

Something like this?:

That's it! Thank you!

what a beautiful trilium!!!
tri, meaning 3, 3 petals, 3 leaves.
I've seen them a paler color, sometimes cream colored.
that one is so bright, wow!

Any thought on how and when to transplant?

First let me say that that is not my picture, just one that I found on the web!

They can be transplanted now and over the next several weeks (months?) until they go dormant and you can't find them any more.

It varies on how deep the base of the plant is, depending on the soil. Usually about 4 inches, could be more or less. Here is a picture of what it looks like (again not my picture):

There are several different kinds of trillium.
If you saw a paler one it was probably a different species.

Nice root picture though.

Hi Kmorrel
In some states wild Trillum is an endangered or threatned species. Please Check with your local conservation district if you plan to remove it from the wild.

The original poster says in the original post that the plant is on their property ("our woods").

Our trillia (trilliums?) are white only. I have carefully moved a few to a spot closer to the house (with the same soil and sunlight) so that I can see them from the window, but they haven't all made it, so I've resigned myself to leaving the rest of them where they are. They seem very sensitive to even the slightest change.

Agertz, I can't imagine why your plants are not coming back. I have rescued probably thousands of trilliums, mainly cuneatums, erectums, sulcatums, ruegelii, and even grandiflorums, the big white ones. There are other white ones, of course, that do not grow in our area, so I have not worked with them. Most trilliums require at least moderately good soil, but I just had a site that was hard, red clay,and they had thrived there...before the bulldozer. If we don't have enough rain in the summer, they just go dormant early.I have planted many here at my house, put some in public gardens, and given many away. Nobody says they never come back. Can you give any more details? You should be able to move these plants. They are not as particular as ladyslippers. Check your soil Ph although, since you are only moving them a short distance, it is probably the same. I did buy some T. flexipes that like a more neutral soil, and I had to put a chunk of concrete nearby to help them along, but that is all the amendments that I have done. They bloomed beautifully this year. The only trillium that I have had trouble with is T. pussilum. Can anybody out there help with growing ideas for this one? Oh, we transplant any time since rescues are dependent on the developer, and most of the trillium respond ok. The photo and the rhizome drawings were quite good...the latter shows the "L" shape that, when digging, you have to make allowances for so that you do not cut the rhizome.