Ask Mr. Smarty Plants

Cercis canadensis (eastern redbud) is native to Missouri, grows 15 to 30 ft. tall, is deciduous, blooms pink March to May, has low water use, needs part shade or shade and moist, fertile, well-drained soil.

Here are the Propagation notes from our webpage on this plant:

Propagation

Description: The simplest way to grow redbuds is to scarify seeds and plant outdoors in the fall. Cuttings are nearly impossible. Seedlings which may develop around mature trees are easily moved when very small.
Seed Collection: Harvest legumes when they turn brown and begin to dry. Early collection may minimize weevil damage. Collect large amounts to compensate for a high percentage of unsound seed. Air-dry seeds and store in sealed, refrigerated containers.
Seed Treatment: Scarify for 10-20 minutes in concentrated sulfuric acid, then stratify for 30-60 days at 41 degrees.
Commercially Avail: yes

In answer to your question, it's hard to know if you have suckers coming up from roots or plants coming up from seeds. The roots may extend much farther than you realize, and still be producing suckers. Our recommendation is that you go in under some of the little plants with a shovel or trowel, scooping out as much earth beneath it as you can. If you hit a large root, and can't get the shoot out without breaking it off, that's probably a sucker. If you feel you have an actual rooted plant, get some of the excess soil off of it, and get it into a pot of good quality potting soil. We would also suggest that you make arrangements to take several of these transplants, to allow for a failure rate. Don't fertilize, the potting soil probably has some nutrients in it, and you don't want to shock the little roots. Keep it in light shade, and make sure the soil is kept moist, but not soggy. Drainage is important, you need a pot with drainage holes. When, and if, you get some good, vital plants going, transplant again, this time into your garden. This should be done in late Fall or early Spring in Missouri. Hopefully, by then there will be ample roots to hold a soil ball together. Dig a hole in an appropriate place, larger than the root ball the plant has formed. Make sure the plant stays moist in the ground, as well, but that water does not stand on the surface. A good idea is to prepare the area where you intend to make the permanent planting with some compost, which will help with the drainage and assist the little roots with access to trace nutrients in the soil. Again, don't fertilize, at least until Spring. The plant will be semi-dormant, anyway, and the composted soil should be adequate.

Cercis canadensis

Cercis canadensis

Cercis canadensis

Cercis canadensis