Another thing to consider, wild seng often grows and does well in grown up places. Sometimes I use my long handle digger to push the weeds and briars back and WOW there is a nice 4 prong. I have found lots of nice big old seng plants growing in thick mess like that expecially in the edge of clear cuts where there was lots of sun geting thru in the morning hours, then it was shaded fairly well in the evenings.
When it comes to planting, it would be ideal to plant in beds as others have suggested, but that is sure not the only way to do it.
You could just get in there and poke a hole and plant a seed, or perhaps with a leaf rake, just rake back a 4x4 or 6x6 or even 2x2 spot where ever you can and plant your seeds at 4-5 per sq ft. In areas where it is real thick, reduce your seeding rate to more like 2-3 per sq ft - to help with possible disease issues. Removing the underbrush increases airflow and helps to reduce disease, if you can't reasonably do that in some places then reduce your seeding rate to help wiht that some.
When it comes to planting in beds, that is very advisable if you are going to have to add soil supplements like gypsum, and would also make it easier at harvest time, but now if your soil does not need any ammendments, calcium is good, ph is good, healthy seng does grow there, then I would sure consider ditching the large bed approach and just do what you can without killing yourself to clear large areas.
Good Luck !
TNhunter