I was at the Riverbanks recently. The freeze did hit hard, and did kill a lot of the La Mortola blooms. They do have a big noisette collection, and some huge climbers. They also have a lot of found roses from SC. Definitely worth a visit, and hopefully you'll get there for a flush of flowers in June. Another great garden about 35 minutes south is the Edisto Rose Garden in Orangeburg. They have a substantial collection of mostly modern roses. And of course, Roses Unlimited at exit 44 off I-26. Riverbanks does a no spray garden, and Columbia has to be one of the hotter/humid places on the East Coast. The other plant they have a lot of are Crinums- a left over from the Jenks Farmer days.

Anyone who's used Al's 5-1-1 or any of the other bark-heavy container mixes knows just how excellent pine bark fines are as both a container substrate and soil amendment. One of my garden beds is situated at the foot of a steep bank that I've been trying to stabilize for a number of years using annual additions of pine bark mulch. Every winter, a good deal of the mulch is blown and deposited in the garden - probably a good 1" of finely textured mulch each year. That bed is consistently my best performer - and, when I pull a soil sample for testing - it is as close to ideally balanced as any of my beds. Having said this, I wouldn't anticipate hardwood chips to perform nearly as well. As kimmr pointed out, there's no "secret" to the system. It's simply consistent addition of copious amount of organic matter. I would add two that, since the wood chips (and I'm assuming a preponderance of conifer wood chips in Gautschi's situation) are very slow to decompose, they provide a better source of OM than some other options. Also, I would guess that the lignins and other chemical components of conifer bark would result in a high level of pure humus once it's fully decomposed.

Let me suggest something else here. Black locust is often deliberately planted to stabilize the kind of steep, sandy soil you have. Felling large black locust trees will not eliminate them. Black locusts sucker from the roots more vigorously than almost any other tree species and it is the mass of roots and the ability of this species to utilize atmospheric nitrogen that makes it so valuable in land reclamation, erosion control and stabilization. (In addition, they are beutiful in bloom and an important nectar source for bees and other insects). In short, black locust will always be present barring massive root excavation or herbicide use and you are probably much better off with them than without them. I would get rid of the Norway maples and box elders when they are small enough to deal with - both are invasive and weedy trees with little to recommend them. Finally, I have no idea what state regulations are for you, but I'd certainly check before doing anything this close to a creek.

You didn't say if you had sandy or clay soil. I have clay soil and greens, green beans and sugar snap peas do well. Other than that I do everything in containers. When I had sandy soil everything except tomatoes did well, again, I had to grow tomatoes in containers. I pretty much plant everything by seed.