Thanks all. Yes, Blueberries - and especially if I have pine forests to acidify the soil for them!
Sandy, yes, I've been thinking of a variety of mushrooms. Aside from those that will self-spore, there are a lot of felled hardwoods which would be ideal for inoculation. And absolutely to Japanese Knotweed. Aside from culinary uses, this plant is widely used now as part of a herbal regimen to help with Lyme disease, so there are a lot of places to use that.
Walt, yes, understood. This is why I'm looking for things to grow that I can harvest on a shorter time frame, to keep the rent paid while I wait for the Ginseng (and others - Goldenseal, for one) to come to adult, harvestable stage.