Aucuba japonica (Japanese laurel) is often recommended for situations like this. Very tolerant of shade - even full shade - and dry soil conditions. Also will compete quite successfully with tree roots, so easier to establish than some other shrubs. And variegated forms can bring some color and brightness to a deeply shady location. Here is a link that might be useful: Aucuba links

My hydrangea arborense Annabelle take pretty dry conditions and propagate quite easily through cuttings or by putting a brick on a branch midsummer for a couple of months to get it to root. That way by buying a few plants you can end up with a bunch. Similarly my aucuba japonica gives many babies by seeding nearby. (Can you grow it in NY?) PG hydrangea limelight provided children through stems that I used as stakes. I haven't done this yet, but I'll bet a brick on a branch will get you a baby. I bought a fresh bunch of curly willow branches at a farmers market for decoration in the house. I put them in a vase with water and they rooted. I potted them and I now have a forest of curly willow saplings that I cut. (Warning do not put anywhere near your water or drain systems. Mine are 50 feet away.) Forcithia stems which are sold by the bundle can also be rooted this way. But nothing beats a nursery that is dumping shrubs onto the market.

whaas - I generally don't like yellow/gold (which might seem a bit strange since our house is yellow!) So I have almost no yellow flowers in the garden and, up until recently, had very few yellow foliage plants - they always look sick to me :-) However, I have come to see that the best way to use yellow plants is to mass them together - hence the golden path idea. My 'lightbulb moment' re yellow came a few years ago on a local garden tour when I was bowled over by the combination in the picture below. There were a number of other 'yellow' plants in the garden but they were mixed in with other - heavily 'blue' type - plants. The gardener was obviously trying for a yellow and blue themed garden but it came off as a bit insipid. But it struck me that what would have made a very striking and beautiful garden was to mass all the yellow stuff together. I've been looking for an excuse to try it ever since... :-) My SIL planted some yellow globe cedars near their front door a couple of years ago and I suggested she plant the Golden Forest Grass with them. She did and that makes a beautiful combination - and reinforced my desire to try for a yellow grouping. We'll see how it turns out.... Have you considered running a soaker hose in the area to provide supplemental water? I used soakers to start the garden under the pines. After the first couple of years I didn't need to use them anymore. So far, even the Golden Forest Grass is surviving under the pines even though it's supposed to prefer moist soil. If the plants aren't too expensive, I always push the limits on the moisture issue. For instance, Rodgersias are supposed to prefer moist soil but they do best for me in soil on the dry side in shade. Astilboides, on the other hand, most definitely needs lots of moisture and do wonderfully well planted at the base of downspouts from the eavestroughs! Experiment, experiment...

I would also suggest the eleutherococcus. I have two, one closer to the silver maple (and under the canopy all day). Of the two, the one that is farther away is a bit taller, but both are holding their own and the bright leaves look nice in the deep shade. During last summer's really dry spell, I watered the one closest to the tree several times. This year, we've had so much rain that, even now, in mid-June, the soil in the maple's root zone remains damp. The shrubs I have now were planted as sticks in the summer of 2006 and are about 3' high. With more sun and more reliable water, they would grow a good bit faster. The one in my z5 garden was 5' tall by the end of its third growing season and was filling out well.