Thanks for the words of wisdom (& encouragement). I certainly would have ammendend the soil in the planting hole out of habit! i will get DH busy sharpening my tools. I want to plant mostly low growing things so as not to block our view of the water (we're on a lake). But it's the water view that makes us spend so much time gazing out through these woods and why I want to "improve" it. Anyone else have any additional tips?

Hostas and Astilbe need a lot of water, relatively speaking. I do not think they will ultimately do well in the conditions you describe.

In any case, here are some plants that I like to recommend for "dry shade", i.e. areas typically with root competition:

Alchemilla mollis (Lady's Mantle)
Bergenia
Geranium à cantabrigiense (Cambridge Cranesbill)
Geranium macrorrhizum (Bigroot Cranesbill)
Geranium sanguineum (Bloody Cranesbill)
Lamiastrum (False Lamium)
Lamium
Podophyllum peltatum (May Apple)
Polygonatum (Solomon's Seal)
Viola labradorica (Labrador Violet)

Hope this helps.

I'm going to have to respectfully disagree with one aspect of ladywindsurfer's advice. When you sever roots with a shovel or tiller it stimulates the regrowth of those roots. Sometimes it is necessary to dig in order to plant something large like a shrub. In that case, make a wide shallow hole to give the shrub a fighting chance. In all other cases it's better to add a mixture of partially decomposed leaves, bark, sand on top and plant into that.

Mainegrower, can you be more specific? What ratio leaves to sand? And why decomposed leaves, sand, etc. rather than dirt? Thanks.

I have 4 huge silver maples that have the same difficult root system you describe. I have had fine luck digging holes as small as possible with a sharp shovel and planting with added soil since it's hard to come by in those root masses. I then watered the individual plants really well for a couple of weeks. I planted persicaria, 'Painter's Palette'; Hosta, 'Honey Bells; Lamiastrum; Ranunculus reptans; native white achillea; Loosestrife, (gooseneck); Symphytum, (not variegated); and Ribbon Grass. I also tried some variegated hosta that lived but didn't thrive. -Large plain green ones seem to do best. Gooseneck is shorter with smaller blooms and less spread but does fine. I tried ferns but they just wasted away. I planted lamium last year - verdict's still out until I see how it comes back this year. I also planted native toad lily (blue flowers), that does well but I don't know where you could get it. I may try some epimedium this year.

The roots under those trees are so bad that I dumped some excess shredded mulch there once for later use. When I needed it about 6 weeks later, I couldn't shovel it because it was so full of roots. I had to work (and I do mean work) it loose with a garden rake. -Don't do that anymore!

Hope this helps. Also could try Brunnera - probably not variegated.

Hello All,gslgal
My first time posting on this forum.
You mentioned planting bulbs and ferns, so you don't really need a shovel sized hole, right? U need to get thru the fiberous roots.
Well, i just finished using a simple tool i found at Home Depot, sold as a "bulb planter". It's about 2.5' long, has a T-handle with a release lever. Down on the business end is a cylinder(a cone actually) about 3" in diameter and 5" deep, so it removes a plug of "soil". You stand,jump on it to drive it down, pull it out, squezze the release handle and the plug drops out. In theory.
I, just this week, finished planting 407 longleaf pine seedlings "out at the camp". I used this thing rather than the traditional dibble and was impressed. Strong, well made cost $35 or so. I also filed the edge sharper as soon as i got it, just for good measure. maybe this tool will work for you too.

The ratio of the sand, leaves, bark mixture is not at all critical. The reason for using it instead of dirt is that you need to add a good depth of the mixture. "Dirt" almost always contains a high percentage of clay which will compact and limit the amount of oxygen available to plant roots. What you're really doing is artificially creating the deep layer of humus found in woodlands where the roots have not overwhelmed everything. The tree roots will eventually penetrate, but if you keep adding to the humus layer yearly, many plants can coexist with the roots.

There was a very good article about this technique in the journal of the North American Rock Garden Society some years ago. It may be archived on line. William Cullina's book about growing native woodland plants also has excellent advice.

I too have a maple tree to plant under. Trouble is, they are not only greedy feeders, the roots tend to come up into any soil or mulch you put over them. They also tend, like the black walnuts, to be somewhat alleopathic and don't want just anything growing under them. I have tried a plethora of shade plants under them, but have had success with only a few. Common violets do well, as does ajuga. I also grow rudbeckia, coneflowers and bidens. Iris, daylilies, acanthus, chrysanthemums, amsonia, irises, baptisia, coral bells, ground cover sedums, and spiderwort all grow at the edge of the root line, but hostas and ferns hate it. Forsythia and nandina grandiflora share root space and hold their own, as does an autumn clematis that grows up the trunk. Maples also don't like grass growing under there and competing for water and nutrients, so that is usually killed out.

I live in the rocky, tree-rooty hills of the Ozarks, and still grow wildflowers under the trees in my woods. I use a small hand pick to make holes in the rocky, rooty soil, and drop in bulbs or put a bit of garden soil in a hole just big enough for a plant to give it a start, and that usually works. Sometimes I have to resort to a regular size pick or mattock, but I never dig up a whole area, just make individual holes. I find sometimes that if you injure the bigger roots of some trees they will send up suckers in those spots for you to deal with, so if I run into a big root I just move over to an emptier spot. Plants that compete very well include mayapples, Solomon's seal, wild geraniums, wild ginger,lily of the valley, ferns and hostas (except under maples, hellebores, arums, sedums, and daffodils hold their own no matter how many rocks and roots there seem to be. I also try to plant small so I don't have to dig a very big hole, and smaller plants seem to adjust better.

This is a lot of helpful information. When we moved to our woods four years ago I knew very little about gardening or tree roots. I made a raised flower garden between two maple trees just to the south of them. In no time I had tree roots coming up into the garden. Everything I planted is doing well, but I found that I can't dig a hole bigger than for a small seedling anymore so have been starting my own flowers from seeds the last two years. Some will seed themselves down.

part of the thing about planting among tree roots is that you have to locate the correct type of plants. The ones you need to plant must have most of their roots below the root area of the trees. Therefore things with long roots, tap or fiberous will be able to stabilize before the tree roots grow back. Another thing is to think of the type of plants that do grow in wooded areas. Many just come up, bloom, make a little foliage to store energy for next year and die. Bulbs are in this group. Others such as asters put out expanding deep roots.

Hmmm maybe I should have read this thread before embarking on the project described below.
On the edge of the lawn there are mature hemlock trees under which I've planted hostas. These have done well and the soil there is moist (lots of rain this year), deep and black.
Behind the hemlocks the ground slopes down and the area is comprised of mature deciduos trees - mosty red maple. Although the soil here is dry and full of fiberous roots I decided to plant hostas. Useing shovel, mattock and axe I dug large holes - at least as large as I thought a mature hosta root ball would be. I lined the hole with landscape fabric and filled with topsoil, compost, dehydrated manure, peat moss and planted hosta. This was pretty exhausting and could only do about two holes a day.
A few years ago I started a compost pile on the edge of woods where there were maple tree roots. Under half the pile I put down filter fabric and on the other half landscape fabric. The tree roots had penetrated the filter fabric but not the landscape fabric. Hopefully this will keep the tree roots at bay. Time will tell.

I would probably try some more intrusive plants myself, and let them figure out how to 'break in'. Creeping thyme, vinca, etc... once they are established, hey should help to break the soil, and you should be able to peel them back to make holes for your new plants. Then the majority of your maintenance would be to continue peeling them back, or to construct a physical barrier to keep them at bay. I built a large rock garden on top of a root bed, using river stone and filter cloth as a barrier between the tree roots and my new garden where I grow covers, hens and chicks, ferns and Jacob's Ladder as well as some spruce shrubs and Calgary carpet. Hope this helps. Sometimes thinking outside the box and working beside rather than against nature is easier.

There are lots of woodland perennials which hate summer moisture. They often thrive in a root-congested planting area, because the thirsty tree roots wick the excessive moisture away. Examples in my woodland which love the tangled root competition include bloodroot and cyclamen.

I planted cyclamens once. The squirrels ate them the first day. Darn tree rats!