I have tigers eye Sumac growing under two maple trees. They need sun, but do fine in an area that gets Some sun. Mine, in the late afternoon and evening when the sun is low. It does not bloom, but the colors are stunning.
I also have a nine-bark in morning dappled sun. They are native and come in many leaf colors and sizes. The benefit to these plants are they are survivors, even in that horribly dry year, they looked great. I planted a Pee-Wee Hydrangea in a spot that gets only about four hours of early morning sun. I thought it would be small (peewee...who knew?) it grows well over 6' and the blooms are huge, drying on the woody stems to last all winter. Not all hydrangea are the same.
I have a Doublefile Viburnum in full shade. They are gorgeous, but huge. HUGE. The plus to them is that they produce a berry that feeds the birds. there are many Viburnums, not all re as pretty not all berry, not all get as large, but all are very hardy and do well in shade.

I don't really have that much advice, I just wanted to say I'm sorry you lost your friend of 26 years. Always very hard to lose a beloved animal.

Regards,
Don B.

P.S. One idea...In my opinion, hostas are always nice, do well in shady areas, and there are many varieties to choose from. I've included a link for browsing at your leisure.

Here is a link that might be useful: The Hosta Library website

Sorry to hear about your horse.

I did want to mention that spirea do very well in the shade. Both the house I grew up in and my neighbor's house have spirea on the north side and they get zero sun, albeit bright shade, and they are vigorously growing. I'm not certain of the variety though.

Thanks, all! Still thinking about it! Ohhh, I LOVE tiger eye sumac!! I have one, just a small one. But this spot would provide only morning, dappled sun so probably not a reasonable choice. Thank you for the info on spirea, I know sometimes what the tag says, and what they really like, are two different things. I love persian shield, for example. Most tags say part sun to sun. I have learned through experience that they prefer part shade to shade, actually. Mine scorch in the sun....

I love hostas, and have many different kinds in my yard. I know I plan to put some of those in. One thing I have to keep in mind is care/water requirements, because I do have to haul water up there.

My plan, is to have a plan by spring so I can just get to work! All I've come up with so far are the hostas, and a tree swing up there somewhere. It really is my special spot....like a get-a-way vacation on my own property!

Since it is a distance from a water supply, and sounds like a mostly natural setting, I would suggest mostly native woodland plants for your region. Being suited to the environment, once they are established they should require less maintenance and supplemental watering.

Although it isn't native, and is supposed to require part shade to full sun and regular watering, glossy abelia is doing very well in the filtered light under tall oaks in my very well-drained sandy soil, and I hardly ever provide supplemental water. It is semi-evergreen and blooms all summer long, attracting butterflies, native bees, and hummingbird moths. I'm in Zone 7, however, and I see you're in 5.

Some great perennial native groundcovers for dry shade are coral bells (heuchera), tiarella, heucherella (a cross between the two). These come in so many colors and variegations, they provide color even when not in bloom.

Not native, but well suited to dry shade is sweet box (sarcococca) which is a low-growing evergreen shrub, spreads politely, and has tiny but very fragrant flowers in late winter/very early spring. Epimedium is another delight - tiny flowers on wiry stems seem to hover above the foliage. Camellia likes shade, can tolerate dry shade well, and will provide flowers in winter - the ones that bloom in December are a safer bet, as the buds of the later bloomers can suffer frost damage. There are small irises (not the tall bearded ones) that are right at home in the forest setting. Primroses for early spring color. Many early spring bulbs will bloom and the leaves mature before the trees have leafed out significantly, allowing more sun to reach the woodland floor.

And, of course, ferns just belong in the woods, and they create a wonderful ambiance.

With the exception of the glossy abelia, none that I've mentioned bloom all season, but the right mix will provide you with something new to find each visit as the seasons progress.

Ferns never even crossed my mind! I will definitely put some of those up there!!