Is it legal to pick wild orchid for sale in the US?

[Subrosa]

Poaching is illegal wild collection. It's quite possible to legally collect wild orchids, depending upon the state you're in. Here in PA, any native plants which are not federally protected can be collected on private property with landowner permission. Most of our natives are autotrophic species which are quite capable of feeding themselves once they reach a certain stage of development. Mycorrhizae are only needed for germination and early development of these species. True mycoheterotrophs like coralroots are a different matter entirely, and should never be wild collected. There has been some work in Japan with their native mycoheterotrophic species, and there has been limited success with growing, blooming and then growing successive generations from the seed produced, but I'm unaware of any success with US native mycoheterotrophs. The difficulty in transplanting terrestrial species varies widely. Most bog species are stupid easy, not just for orchids but for plants in general. Just keep them sopping wet after transplanting and losses are minimal. Growing Pogonia species is very easy, providing you can grow Sphagnum moss. Cypripedium are a special case, mostly due to the unusual nature of their root systems. And C. acaule is extra difficult due to its demanding very specific soil conditions. Typical plants have roots that grow deep into the soil in search of moisture and nutrients, and digging them for transplanting is simply a matter of working around the dripline (the spread of the branches) and going deep enough to get the bulk of the roots. Cypripedium roots grow horizontally a couple inches below the surface, and radiate out like the spokes of a wheel. A first bloom C. acaule will have a root system 2'-3' in diameter, and if you dig at the dripline you cut off the vast majority of the roots, condemning the plant to death regardless of how good the conditions are that you transplant it into. The special difficulty with acaule is that it requires extremely acidic conditions to inhibit bacteria which will cause them to rot. There is at least one company I know of that grows them from seed in vitro. Under sterile conditions the seeds germinate and grow well at a slightly acidic pH, almost approaching neutral. But once they come out of the flasks they will quickly rot if not put into a substrate with a pH below 5.0, the lower the better. It's recommended to water them with a solution of 1 tablespoon of distilled white vinegar per gallon of rainwater, ro or distilled. Unless you're truly blessed, your tapwater is the kiss of death for them. Living here in the Appalachians of PA, acaule are actually quite common. I collected a tiny one a couple years back from a neighbor's property with permission and planted it in a high spot in my carnivorous plant and orchid bog. I suspect it may bloom this year. One other thing about Cypripedium is that squirrels and chipmunks eat them like potato chips, so if that's a possibility you'll want to take precautions. I cleared away some of the pine needles and got this pic of mine just emerging from the peat/sand substrate of the bog: